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Name Class Date
Resource Locker
Explore Interpreting Parts of an ExpressionAn expression is a mathematical phrase that contains operations numbers andor variables The terms of an expression are the parts that are being added A coefficient is the numerical factor of a variable term There are both numerical expressions and algebraic expressions A numerical expression contains only numbers while an algebraic expression contains at least one variable
Identify the terms and the coefficients of the expression 8p + 2q + 7r
terms coefficients
Identify the terms and coefficients of the expression 18 - 2x - 4y Since the expression involves rather than addition rewrite the expression as the of the terms
18 - 2x - 4y = So the terms of the expression areand the coefficients are
Identify the terms and coefficients in the expression 2x + 3y - 4z + 10 Since the expression involves both and addition rewrite the expression as theof the terms 2x + 3y - 4z + 10 = So the terms of theexpression are and the coefficients are
Tickets to an amusement park are $60 for adults and $30 for children If a is the number of adults and c is the number of children then the cost for a adults and c children is 60a + 30c
What are the terms of the expression
What are the factors of 60a
What are the factors of 30c
What are the coefficients of the expression
Interpret the meaning of the two terms of the expression
The price of a case of juice is $1500 Fred has a coupon for 20 cents off each bottle in the case The expression to find the final cost of the case of juice is 15 - 02b wherein b is the number of bottles
What are the terms of the expression
Module 2 45 Lesson 1
2 1 Modeling with ExpressionsEssential Question How do you interpret algebraic expressions in terms of their context
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What are the factors of each term is the only factor of the
term and and are the factors of the term
Do both terms have coefficients Explain
What are the coefficients
What does the expression 15 - 02b mean in the given situation
Reflect
1 Sally identified the terms of the expression 9a + 4b - 18 as 9a 4b and 18 Explain her error
2 What is the coefficient of b in the expression b + 10 Explain
Explain 1 Interpreting Algebraic Expressions in Context In many cases real-world situations and algebraic expressions can be related The coefficients variables and operations represent the given real-world context
Interpret the algebraic expression corresponding to the given context
Example 1
Curtis is buying supplies for his school He buys p packages of crayons at $149 per package and q packages of markers at $349 per package What does the expression 149p + 349q represent
Interpret the meaning of the term 149p What does the coefficient 149 represent
The term 149p represents the cost of p packages of crayons The coefficient represents the cost of one package of crayons $149
Interpret the meaning of the term 349q What does the coefficient 349 represent
The term 349q represents the cost of q packages of markers The coefficient represents the cost of one package of markers $349
Interpret the meaning of the entire expression
The expression 149p + 349q represents the total cost of p packages of crayons and q packages of markers
Jill is buying ink jet paper and laser jet paper for her business She buys 8 more packages of ink jet paper than p packages of laser jet paper Ink jet paper costs $695 per package and laser jet paper costs $8 per package What does the expression 8p + 695(p + 8) represent
Interpret the meaning of the first term 8p What does the coefficient 8 represent
The term 8p represents the cost of The coefficient represents $8
Interpret the meaning of the second expression 695(p + 8) What do the factors 695 and (p + 8) represent
Module 2 46 Lesson 1
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The term 695(p + 8) represents 695 represents the cost of (p + 8) represents that Jill bought
Interpret the expression 8p + 695(p + 8)
The expression represents that Jill bought
Your Turn
Interpret the algebraic expression corresponding to the given context
3 George is buying watermelons and pineapples to make fruit salad He buys w watermelons at $449 each and p pineapples at $5 each What does the expression 449w + 5p represent
4 Sandi buys 5 fewer packages of pencils than p packages of pens Pencils costs $225 per package and pens costs $3 per package What does the expression 3p + 225(p - 5) represent
Explain 2 Comparing Algebraic ExpressionsGiven two algebraic expressions involving two variables we can compare whether one is greater or less than the other We can denote the inequality between the expressions by using lt or gt symbols If the expressions are the same or equivalent expressions we denote this equality by using =
Suppose x and y give the populations of two different cities where x gt y Compare the expressions and tell which of the given pair is greater
Example 1
x + y and 2x
The expression 2x is greater
bull Putting the lesser population y together with the greater population x gives a population that is less than double the greater population
x _ y and y _ x
Since x gt y x _ y will be than 1 and y _ x will be than 1
So x _ y y _ x
Your Turn
Suppose x and y give the populations of two different cities where x gt y and y gt 0 Compare the expressions and tell which of the given pair is greater
5 x _ x + y and x + y
_ x 6 2(x + y) and (x + y)2
Module 2 47 Lesson 1
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Explain 3 Modeling Expressions in ContextThe table shows some words and phrases associated with the four basic arithmetic operations These words and phrases can help you translate a real-world situation into an algebraic expression
Operation Words Examples
Addition the sum of added to plus more than increased by total altogether and
1 A number increased by 22 The sum of n and 23 n + 2
Subtraction less than minus subtracted from the difference of take away taken from reduced by
1 The difference of a number and 22 2 less than a number3 n - 2
Multiplication times multiplied by the product of percent of
1 The product of 06 and a number2 60 of a number3 06n
Division divided by division of quotient of divided into ratio of
1 The quotient of a number and 52 A number divided by 53 n divide 5 or n __ 5
Example 3 Write an algebraic expression to model the given context Give your answer in simplest form
the price of an item plus 6 sales tax
Price of an item + 6 sales tax
p + 006p
The algebraic expression is p + 006p or 106p
the price of a car plus 85 sales tax
The price of a car +
+
The algebraic expression is
or
Reflect
7 Use the Distributive Property to show why p + 006p = 106p
8 What could the expression 3(p + 006p) represent Explain
Your Turn
Write an algebraic expression to model the given context Give your answer in simplest form
9 the number of gallons of water in a tank that already has 300 gallons in it after being filled at 35 gallons per minute for m minutes
10 the original price p of an item less a discount of 15
Module 2 48 Lesson 1
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Elaborate
11 When given an algebraic expression involving subtraction why is it best to rewrite the expression using addition before identifying the terms
12 How do you interpret algebraic expressions in terms of their context
13 How do you simplify algebraic expressions
14 Essential Question Check In How do you write algebraic expressions to model quantities
bull Online Homeworkbull Hints and Helpbull Extra Practice
Evaluate Homework and PracticeIdentify the terms and the coefficients of the expression
1 -20 + 5p - 7z 2 8x - 20y - 10
Identify the factors of the terms of the expression
3 5 + 6a + 11b 4 13m - 2n
5 Erin is buying produce at a store She buys c cucumbers at $099 each and a apples at $079 each What does the expression 099c + 079a represent
6 The number of bees that visit a plant is 500 times the number of years the plant is alive where t represents the number of years the plant is alive What does the expression 500t represent
Evaluate Homework and Practice
Module 2 49 Lesson 1
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Leonard
LenzC
orbis
7 Lorenzo buys 3 shirts at s dollars apiece and 2 pairs of pants at p dollars a pair What does the expression 3s + 2p represent
8 If a car travels at a speed of 25 mih for t hours then travels 45 mih for m hours what does the expression 25t + 45m represent
9 The price of a sandwich is $150 more than the price of a smoothie which is d dollars What does the expression d + 15 represent
10 A bicyclist travels 1 mile in 5 minutes If m represents minutes what does the expression m __ 5 represent
11 What are the factors of the expression (y - 2)(x + 3)
12 Explain the Error A student wrote that there are two terms in the expression 3p - (7 - 4q) Explain the studentrsquos error
13 Yolanda is buying supplies for school She buys n packages of pencils at $140 per package and m pads of paper at $120 each What does each term in the expression 14n + 12m represent What does the entire expression represent
14 Chris buys p pairs of pants and 4 more shirts than pairs of pants Shirts cost $18 each and pair of pants cost $25 each What does each term in the expression 25p + 18(p + 4) represent What does the entire expression represent
Module 2 50 Lesson 1
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alke
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In Im
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Cor
bis
Suppose a and b give the populations of two states where a gt b Compare the expressions and tell which of the given pair is greater or if the expressions are equal
15 b _ a + b
and 05
16 a + 13c and b + 13c where c is the population of a third state
17 a - b _ 2 and a - b _ 2
18 a + b and 2b
19 5(a + b) and (a + b)5
Write an algebraic expression to model the given context Give your answer in simplest form
20 the price s of a pair of shoes plus 5 sales tax 21 the original price p of an item less a discount of 20
22 the price h of a recently bought house plus 10 property tax
23 the principal amount P originally deposited in a bank account plus 03 interest
Module 2 51 Lesson 1
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pany
24 Match each statement with the algebraic expression that models it
A the price of a winter coat and a 20 discount x + 002x = 102x
B the base salary of an employee and a 2 salary increase x - 020x = 080x
C the cost of groceries and a 2 discount with coupons x + 020x = 120x
D the number of students attending school last year and a 20 increase from last year x - 002x = 098x
HOT Focus on Higher Order Thinking
25 Critique Reasoning A student is given the rectangle and the square shown The student states that the two figures have the same perimeter Is the student correct Explain your reasoning
26 Multi-Step Yon buys tickets to a concert for himself and a friend There is a tax of 6 on the price of the tickets and an additional booking fee of $20 for the transaction Write an algebraic expression to represent the price per person Simplify the expression if possible
x + 2
x + 2x
x + 4
Module 2 52 Lesson 1
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27 Persevere in Problem Solving Jerry is planting white daisies and red tulips in his garden and he wants to choose a pattern in which the tulips surround the daisies He uses tiles to generate patterns starting with two rows of three daisies He surrounds these daisies with a border of tulips The design continues as shown
a Jerry writes the expression 8(b - 1) + 10 for the number of tulips in each border wherein b is the border number and b ge 1 Explain why Jerryrsquos expression is correct
b Elaine wants to start with two rows of four daisies Her reasoning is that Jerry started with two rows of three daisies and his expression was 8(b - 1) + 10 so if she starts with two rows of four daisies her expression will be 10(b - 1) + 10 Is Elainersquos statement correct Explain
Border 1 Border 2 Border 3
Module 2 53 Lesson 1
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Lesson Performance Task
Becky and Michele are both shopping for a new car at two different dealerships Dealership A is offering $500 cash back on any purchase while Dealership B is offering $1000 cash back The tax rate is 5 at Dealership A but 8 at Dealership B Becky wants to buy a car that is $15000 and Michele is planning to buy a car that costs $20000 Use algebraic expressions to help you answer the following questions
a At which dealership will Becky get the better deal How much does she save
b At which dealership will Michele get the better deal How much does she save
c What generalization can you make that would help any shopper know which dealership has the better deal [Hint At what price point would the two deals be equal]
copy H
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Tom G
rillC
orbis
Module 2 54 Lesson 1
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Name Class Date
Resource Locker
Explore Creating Equations from Verbal Descriptions
You can use what you know about writing algebraic expressions to write an equation that represents a real-world situation
Suppose Cory and his friend Walter go to a movie Each of their tickets costs the same amount and they share a frozen yogurt that costs $550 The total amount they spend is $1990 How can you write an equation that describes the situation
A Identify the important information
The word tells you that the relationship describes an equation
The word total tells you that the operation involved in the relationship is
What numerical information do you have
What is the unknown quantity
B Write a verbal description
Choose a name for the variable In this case use c for
The verbal description is Twice the cost of plus the cost
of equals
C To write an equation write a numerical or expression for each quantity
and insert an equal sign in the appropriate place An equation is
Reflect
1 How can you use a verbal model to write an equation for the situation described
Module 2 55 Lesson 2
22 Creating and Solving EquationsEssential Question How do you use an equation to model and solve a real-world problem
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igital
Vision
Getty Im
ages
2 Could you write a different equation to describe the situation Explain your reasoning
Explain 1 Creating and Solving Equations Involving the Distributive Property
When you create an equation to model a real-world problem your equation may involve the Distributive Property When you solve a real-world problem you should always check that your answer makes sense
Example 1 Write and solve an equation to solve each problem
A Aaron and Alice are bowling Alicersquos score is twice the difference of Aaronrsquos score and 5 The sum of their scores is 320 Find each studentrsquos bowling score
Write a verbal description of the basic situation
The sum of Aaronrsquos score and Alicersquos score is 320
Choose a variable for the unknown quantity and write an equation to model the detailed situation
Let a represent Aaronrsquos score Then 2 (a - 5) represents Alicersquos score
a + 2 (a - 5) = 320
Solve the equation for a
a + 2 (a - 5) = 320
a + 2a - 10 = 320 Distributive Property
3a - 10 = 320
3a - 10 + 10 = 320 + 10 Addition Property of Equality
3a = 330
3a _ 3 = 330 _ 3 Division Property of Equality
a = 110
So Aaronrsquos score is 110 and Alicersquos score is 2 (a - 5) = 2 (110 - 5) = 2 (105) = 210
Check that the answer makes sense
110 + 210 = 320 so the answer makes sense
B Mari Carlos and Amanda collect stamps Carlos has five more stamps than Mari and Amanda has three times as many stamps as Carlos Altogether they have 100 stamps Find the number of stamps each person has
Write a verbal description of the basic situation
Module 2 56 Lesson 2
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Choose a variable for the unknown quantity and write an equation to model the detailed situation
Let s represent the number of stamps Mari has Then Carlos has stamps
and Amanda has stamps
s + + 3 ( ) =
Solve the equation for s
s + + 3 ( ) =
s + s + 5 + 3s + = Distributive Property
+ = Combine like terms
s = Subtraction Property of Equality
s = Division Property of Equality
So Mari has stamps Carlos has stamps and Amanda
has stamps
Check that the answer makes sense
+ + = the answer makes sense
=
Reflect
3 Would a fractional answer make sense in this situation
4 Discussion What might it mean if a check revealed that the answer to a real-world problem did not make sense
Module 2 57 Lesson 2
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pany
Your Turn
Write and solve an equation to solve the problem
5 A rectangular garden is fenced on all sides with 256 feet of fencing The garden is 8 feet longer than it is wide Find the length and width of the garden
Explain 2 Creating and Solving Equations with Variables on Both Sides
In some equations variables appear on both sides You can use the properties of equality to collect the variable terms so that they all appear on one side of the equation
Example 2 Write and solve an equation to solve each problem
A Janine has job offers at two companies One company offers a starting salary of $28000 with a raise of $3000 each year The other company offers a starting salary of $36000 with a raise of $2000 each year In how many years would Janinersquos salary be the same with both companies What will the salary be
Write a verbal description of the basic situation
Let n represent the number of years it takes for the salaries to be equal
Base Salary A plus $3000 per year raise = Base Salary B + $2000 per year raise
28000 + 3000n = 36000 + 2000n
28000 + 3000n - 2000n = 36000 + 2000n - 2000n Subtraction Property of Equality
28000 + 1000n = 36000 Combine like terms
28000 + 1000n - 28000 = 36000 - 28000 Subtraction Property of Equality
1000n = 8000 1000n _ 1000 = 8000 _ 1000 Division Property of Equality
n = 8
28000 + 3000 (8) = 36000 + 2000 (8)
52000 = 52000
In 8 years the salaries offered by both companies will be $52000
(w + 8) feet
w feet
Module 2 58 Lesson 2
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B One moving company charges $800 plus $16 per hour Another moving company charges $720 plus $21 per hour At what number of hours will the charge by both companies be the same What is the charge
Write a verbal description of the basic situation Let t represent the number of hours that the move takes
Moving Charge A plus $16 per hour = Moving Charge B plus $21 per hour
800 + t = 720 + t
800 + t - t = 720 + t - t Subtraction Property of Equality
800 = 720 + t
800 - 720 = 720 + t - 720 Subtraction Property of Equality
= t
_ = t _
Division Property of Equality
t =
The charges are the same for a job that takes hours
Substitute the value 16 in the original equation
800 + 16t = 720 + 21t
800 + 16 ( ) = 720 + 21 ( ) 800 + = 720 +
=
After hours the moving charge for both companies will be
Reflect
6 Suppose you collected the variable terms on the other side of the equal sign to solve the equation Would that affect the solution
Module 2 59 Lesson 2
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Your Turn
Write and solve an equation to solve each problem7 Claire bought just enough fencing to enclose either a
rectangular garden or a triangular garden as shown The two gardens have the same perimeter How many feet of fencing did she buy
8 A veterinarian is changing the diets of two animals Simba and Cuddles Simba currently consumes 1200 Calories per day That number will increase by 100 Calories each day Cuddles currently consumes 3230 Calories a day That number will decrease by 190 Calories each day The patterns will continue until both animals are consuming the same number of Calories each day In how many days will that be How many Calories will each animal be consuming each day then
Explain 3 Constructing Equations from an Organized TableYou can use a table to organize information and see relationships
Example 3 Construct and solve an equation to solve the problem
Kim works 4 hours more each day than Jill does and Jack works 2 hours less each day than Jill does Over 2 days the number of hours Kim works is equal to the difference of 4 times the number of hours Jack works and the number of hours Jill works How many hours does each person work each day
Analyze Information
Identify the important information
bull Kim works hours more per day than Jill does
bull Jack works hours less per day than Jill does
Formulate a Plan
Make a table using the information given Let x be the number of hours Jill works in one day
Hours Worked Per Day Hours Worked Over 2 Days
Kim
Jill
Jack
Over 2 days the number of hours Kim works is equal to the difference of 4 times the number of hours Jack works and the number of hours Jill works
(3x - 3)(x - 3)
(2x - 1) (2x - 1)
2x
Module 2 60 Lesson 2
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Solve
2 (x + 4) = 4 2 (x - 2) - 2x
2 (x + 4) = (x - 2) - 2x Simplify
2x + = 8x - - 2x Distributive Property
2x + 8 = x - 16
2x + 8 + = 6x - 16 + Addition Property of Equality
2x + = 6x
2x + 24 - x = 6x - x Subtraction Property of Equality
24 = x
24 _ = x _ Division Property of Equality
= x
Jill works hours per day Kim works hours per day and Jack works
hours per day
Justify and Evaluate
Substitute x = 6 into the original equation
2 (6 + 4) = 4 2 (6 - 2) - 2x
2 ( ) = 8 ( ) - 2 ( ) =
Your Turn
Write and solve an equation to solve the problem
9 Lisa is 10 centimeters taller than her friend Ian Ian is 14 centimeters taller than Jim Every month their heights increase by 2 centimeters In 7 months the sum of Ianrsquos and Jimrsquos heights will be 170 centimeters more than Lisarsquos height How tall is Ian now
Height now Height after 7 months
Module 2 61 Lesson 2
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oug
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pany
Elaborate
10 How can you use properties to solve equations with variables on both sides
11 How is a table helpful when constructing equations
12 When solving a real-world problem to find a personrsquos age would a negative solution make sense Explain
13 Essential Question Check-In How do you write an equation to represent a real-world situation
bull Online Homeworkbull Hints and Helpbull Extra Practice
Write an equation for each description
1 The sum of 14 and a number is equal to 17 2 A number increased by 10 is 114
3 The difference between a number and 12 is 20 4 Ten times the sum of half a number and 6 is 8
5 Two-thirds a number plus 4 is 7 6 Tanmayi wants to raise $175 for a school fundraiser She has raised $120 so far How much more does she need to reach her goal
7 Hector is visiting a cousin who lives 350 miles away He has driven 90 miles How many more miles does he need to drive to reach his cousinrsquos home
8 The length of a rectangle is twice its width The perimeter of the rectangle is 126 feet
Evaluate Homework and Practice
Module 2 62 Lesson 2
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oug
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Mif
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Har
cour
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Com
pan
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mag
e C
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(t)copy
Pete
r K
imS
hutt
erst
ock
Write and solve an equation for each situation
9 In one baseball season Peter hit twice the difference of the number of home runs Alice hit and 6 Altogether they hit 18 home runs How many home runs did each player hit that season
10 The perimeter of a parallelogram is 72 meters The width of the parallelogram is 4 meters less than its length Find the length and the width of the parallelogram
11 One month Ruby worked 6 hours more than Isaac and Svetlana worked 4 times as many hours as Ruby Together they worked 126 hours Find the number of hours each person worked
12 In one day Annie traveled 5 times the sum of the number of hours Brian traveled and 2 Together they traveled 20 hours Find the number of hours each person traveled
13 Xian and his cousin Kai both collect stamps Xian has 56 stamps and Kai has 80 stamps The boys recently joined different stamp-collecting clubs Xianrsquos club will send him 12 new stamps per month Kairsquos club will send him 8 new stamps per month After how many months will Xian and Kai have the same number of stamps How many stamps will each have
14 Kenya plans to make a down payment plus monthly payments in order to buy a motorcycle At one dealer she would pay $2500 down and $150 each month At another dealer she would pay $3000 down and $125 each month After how many months would the total amount paid be the same for both dealers What would that amount be
ℓ meters
(ℓ - 4) meters
Module 2 63 Lesson 2
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pany
15 Community Gym charges a $50 membership fee and a $55 monthly fee Workout Gym charges a $200 membership fee and a $45 monthly fee After how many months will the total amount of money paid to both gyms be the same What will the amount be
16 Tina is saving to buy a notebook computer She has two options The first option is to put $200 away initially and save $10 every month The second option is to put $100 away initially and save $30 every month After how many months would Tina save the same amount using either option How much would she save with either option
Use the table to answer each question
Starting Salary Yearly Salary Increase
Company A $24000 $3000
Company B $30000 $2400
Company C $36000 $2000
17 After how many years are the salaries offered by Company A and Company B the same
18 After how many years are the salaries offered by Company B and Company C the same
19 Paul started work at Company B ten years ago at the salary shown in the table At the same time Sharla started at Company C at the salary shown in the table Who earned more during the last year How much more
20 Georgersquos page contains twice as many typed words as Billrsquos page and Billrsquos page contains 50 fewer words than Charliersquos page If each person can type 60 words per minute after one minute the difference between twice the number of words on Billrsquos page and the number of words on Charliersquos page is 210 How many words did Billrsquos page contain initially Use a table to organize the information
Initial number of words
Total number of words after one minute
Module 2 64 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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Mif
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Har
cour
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lishi
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Com
pan
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21 Geometry Sammie bought just enough fencing to border either a rectangular plot or a square plot as shown The perimeters of the plots are the same How many meters of fencing did she buy
HOT Focus on Higher Order Thinking
22 Justify Reasoning Suppose you want to solve the equation 2a + b = 2a where a and b are nonzero real numbers Describe the solution to this equation Justify your description
23 Multi-step A patio in the shape of a rectangle is fenced on all sides with 134 feet of fencing The patio is 5 feet less wide than it is long
a What information can be used to solve the problem How can you find the information
b Describe how to find the area of the patio What is the area of the patio
24 Explain the Error Kevin and Brittany write an equation to represent the following relationship and both students solve their equation Who found the correct equation and solution Why is the other person incorrect
5 times the difference of a number and 20 is the same as half the sum of 4 more than 4 times a number
Kevin Brittany
5 (x - 20) = 1 _ 2 (4x + 4) 5 (20 + x) = 1 _ 2 (4x + 4)
5x - 100 = 2x + 2 100 - 5x = 2x + 2
3x - 100 = 2 100 - 7x = 2
3x = 102 -7x = -98
x = 34 x = 14
(3x + 2) meters
(x + 2) meters
(x + 2) meters
(x - 1) meters
ℓ feet
(ℓ - 5) feet
Module 2 65 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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pany
25 What If Alexa and Zack are solving the following problem
The number of miles on Car A is 50 miles more than the number of miles on Car B and the number of miles on Car B is 30 miles more than the number of miles on Car C All the cars travel 50 miles in 1 hour After 1 hour twice the number of miles on Car A is 70 miles less than 3 times the number of miles on Car C How many miles were there on Car B initially
Alexa assumes there are m miles on Car B Zack assumes there are m miles on Car C Will Zackrsquos answer be the same as Alexarsquos answer Explain
Lesson Performance Task
Stacy Oliver and Jivesh each plan to put a certain amount of money into their savings accounts that earn simple interest of 6 per year Stacy puts $550 more than Jivesh and Oliver puts in 2 times as much as Jivesh After a year the amount in Stacyrsquos account is 2 times the sum of $212 and the amount in Oliverrsquos account How much does each person initially put into his or her account Who had the most money in his or her account after a year Who had the least Explain
Zackrsquos Table Initial Miles
Miles after One Hour
Alexarsquos Table Initial Miles
Miles after One Hour
Amount in Account Initially Amount in Account after One Year
Module 2 66 Lesson 2
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Name Class Date
Resource Locker
Explore Rearranging Mathematical FormulasLiteral Equations are equations that contain two or more variables There are many literal equations in the form of math science and engineering formulas These formulas may seem like they can only be solved for the variable that is isolated on one side of the formula By using inverse operations and the properties of equality a formula can be rearranged so any variable in the formula can be isolated It is no different than how equations are solved by using inverse operations and the properties of equality
How can you solve the equation 42 = 6x
A42 _ = 6x _ What is the reason for dividing
Why divide by
= x By rearranging the equation x was isolated and the solution was found
The mathematical formula for the volume of a rectangular prism B = Vh or V = ℓwh is a literal equation V represents volume ℓ represents length w represents width and h represents height Using inverse operations the formula can be rearranged to solve for any one of the variables that might be unknown Like solving for x a formula can be rearranged to isolate a variable
B In the formula V = ℓwh the variable h needs to be isolated
The operation of is used in the formula The inverse
operation should be used
to isolate
C V _____ = ℓwh _____
V _ =
The formula rearranged in this way can easily produce the height of the rectangular prism when the volume length and width are known
Reflect
1 Using the formula for a rectangular prism rewrite the formula to solve for ℓ
ℓw
h
Module 2 67 Lesson 3
23 Solving for a VariableEssential Question How do you rewrite formulas and literal equations
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otosCorb
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Explain 1 Rearranging Scientific FormulasUse inverse operations to isolate the unknown variable in a scientific formula
The formula for density is D = m __ V Lead has a very high density of 11340 kg m 3 Plastic foam has a very low density of 75 kg m 3 The formula for density can be rearranged to solve for V volume or m mass
Example 1
A A sinker on a fishing line is made of lead and has a volume of 0000015 m 3 What is the mass of the sinker
The density formula can be rearranged to isolate m the mass The values for volume and density can then be substituted into the formula to find the mass
D = m _ V
DV = ( m _ V ) V DV = m
(11340 kg m 3 ) (0000015 m 3 ) = m
017 kg asymp m
B The design for a life preserver requires 03 kilogram of plastic foam to provide proper buoyancy What is the volume of the plastic foam required
Rearrange the density formula to isolate V
D = m _ V
(D) V = m _ V
DV =
DV _ = m _
V =
Now substitute the given values
V = _
V = m 3
Your Turn
2 For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Determine the altitude in feet when t is -275 ∘F and g is 60 ∘F
Module 2 68 Lesson 3
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Explain 2 Rearranging Literal EquationsUsing inverse operations to rearrange literal equations can be applied to any formula The interest formula I = prt is another example of a literal equation In the formula I represents interest p the principal or the initial amount to which interest will be applied r the rate at which interest will be paid and t is the time in years
Example 2
A Find the number of years used in the calculation of a $1000 loan at an interest rate of 5 with interest totaling $600
Solve the formula for t
I = prt
I _ pr = prt
_ pr
I _ pr = t
Substitute the given values Since the interest rate is 5 r = 005$600 __
$1000 middot 005 = t
12 = t
So the length of time for the loan is 12 years
B Determine the interest rate for a $2000 loan that will be paid off in 4 years with interest totaling $640 In order to find the interest rate solve the formula for r
I = prt
I _ = prt _
_ = r
Now substitute the values and simplify
__
( ) ( ) = r
008 = r
So the interest rate is per year
Your Turn
3 The formula y = mx + b is the slope-intercept form of the equation of a line Solve the equation for m
Module 2 69 Lesson 3
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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bull Online Homeworkbull Hints and Helpbull Extra Practice
Solve for the indicated variable in each mathematical formula
1 C = 2πr for r 2 A = 1 __ 2 bh for b 3 y = mx + b for x
4 A = 1 __ 2 (a + b)h for h 5 V = πr2h for h 6 SA = 2πr2 + 2πrh for h
Solve for the indicated variable in each scientific formula
7 d = rt for t 8 PV = nRT for T
9 A = FV - OV _______ T for OV 10 C = Wtc _ 1000 for W
Evaluate Homework and Practice
Elaborate
4 Discussion What could be a reason for isolating a variable in a literal equation
5 Describe a situation in which a formula could be used more easily if it were rearranged Include the formula in your description
6 Essential Question Check-In How do you isolate a variable
Module 2 70 Lesson 3
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cean
C
orb
is
Solve for the indicated variable in each literal equation
11 2p + 5r = q for p 12 -10 = xy + z for x 13 a __ b = c for b
14 h - 4 _ j = k for j 15 x __ 5 - g = a for x 16 5p + 9c = p for c
17 2 __ 5 (z + 1) = y for z 18 g (h + 2 __ 3 ) = 1 for h 19 a(n - 3) + 8 = bn for n
20 Which is a possible way to rewrite the equation y = 3x + 3b to solve for b
A b = y - 3x
_ 3 C b = y - 3
_____ 3x
B b = 3(y - 3x) D b = x(y - 3)
21 Sports To find a baseball pitcherrsquos earned run average (ERA) you can use the formula Ei = 9r in which E represents ERA i represents the number of innings pitched and r represents the number of earned runs allowed Solve the equation for E What is a pitcherrsquos ERA if he allows 5 earned runs in 18 innings pitched
22 Meteorology For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Solve the equation for a If the atmospheric temperature is -655 ∘F and the ground temperature is 57 ∘F what is the altitude
Module 2 71 Lesson 3
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oug
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Rand
y D
uch
aineA
lamy
HOT Focus on Higher Order Thinking
23 Explain the Error A student was asked to use the formula for the perimeter of a rectangle P = 2ℓ + 2w to solve for ℓ The student came up with an answer P - 2w = 2ℓ What error did the student make Explain Then solve for ℓ
24 Multi-Step The formula c = 5p + 215 relates c the total cost in dollars of hosting a birthday party at a skating rink to p the number of people attending If Alliersquos parents are willing to spend $300 for a party how many people can attend
25 Multi-Step The formula for the area of a triangle is A = 1 __ 2 bh in which b represents the length of thebase and h represents the height If a triangle has an area of 192 mm2 and the height is 12 mm what is the measure of the base
Lesson Performance TaskThe following table shows the average low temperatures in Fahrenheit for the city of Boston for several months during the year The formula F = 9 __ 5 C + 32 allows you to determine the temperature in Fahrenheit when given the temperature in Celsius
MonthTemperature in
FahrenheitTemperature in
Celsius
January 22deg
April 41deg
July 65deg
October 47deg
December 28deg
a Use the information given to determine the average low temperatures in Celsius
b Would it ever be possible for the temperature in Celsius to have a greater value than the temperature in Fahrenheit Explain why or why not
Module 2 72 Lesson 3
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Name Class Date
Resource Locker
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oug
hton
Mif
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Har
cour
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Com
pan
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mag
e cr
edit
s copy
Patr
ick
Lan
eSo
mos
Imag
esC
orb
is
Explore Creating Inequalities from Verbal DescriptionsAn inequality is a statement that compares two expressions that are not strictly equal by using one of the following inequality signs
Symbol Meaning
lt is less than
le is less than or equal to
gt is greater than
ge is greater than or equal to
ne is not equal to
You have probably seen a sign at an amusement park saying something like ldquoYou must be at least 48 inches tall to ride this riderdquo This statement could be written as h ge 48 in where h represents the height of a person allowed to ride
Nora is planning a birthday party for her little sister Colleen Norarsquos budget will allow her to spend no more than $50 for party supplies Eight children including Colleen will attend the party and Nora wants to determine how much she could spend on party favors for each child She will also purchase a cake for $10 Write an inequality that represents the situation and find possible solutions
A First let c represent the cost of a party favor for each child Write an expression for the total cost of the party as a function of c
c +
B Which inequality symbol should be used to represent the phrase ldquono more thanrdquo
C Write the inequality that represents Norarsquos budget goal
8c + 10 le
D Suppose Nora finds party favors that cost $4 each Use a value of 4 for c and check to see if this inequality is true
8 middot 4 + 10 le 50
le 50
Module 2 73 Lesson 4
24 Creating and Solving Inequalities
Essential Question How do you write and solve an inequality that represents a real-world situation
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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pany
Is the inequality true
Could Nora buy $6 party favors for all of her guests without going over budget
Reflect
1 Why does an inequality represent Norarsquos budget calculation better than an equation
2 The solution set of an inequality consists of all values that make the statement true Describe the whole dollar amounts that are in the solution set for this situation
Explain 1 Creating and Solving Inequalities Involving the Distributive Property
You may need to use the Distributive Property before you can solve an inequality
Distributive Property If a b and c are real numbers then a(b + c) = ab + ac
The inequality sign must be reversed when multiplying or dividing both sides of an inequality by a negative number
Example 1
A Trina is buying 12 shirts for the drama club She will choose a style for the blank shirts and then pay an additional charge of $275 for each shirt to have the club logo If Trina cannot spend more than $99 how much can she spend on each blank shirt Write and solve an inequality to find the possible cost of each blank shirt
Let s represent the cost of each blank shirt
Write an inequality to represent the situation 12(s + 275) le 99
Use the Distributive Property 12s + 33 le 99
Subtraction Property of Inequality 12s + 33 - 33 le 99 - 33
Simplify 12s le 66
Division Property of Inequality 12s ___ 12 le 66 __ 12
Simplify s le 55
Module 2 74 Lesson 4
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oug
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cour
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pan
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Check your answer
Since s le 55 check a smaller number 12(5 + 275) le 99
Trina can order blank shirts that cost $550 or less 93 le 99 true
B Sergio needs to buy gifts for 8 friends He wants to give the same gift to all his friends and he plans to have the gifts wrapped for an additional charge of $150 each If Sergio spends at least $70 he will receive free shipping on his order Write and solve an inequality to determine how much Sergio needs to spend on each gift in order to receive free shipping
Let g be the cost of one gift
Write an inequality to represent the situation ( g + ) ge 70
Use the Distributive Property g + ge 70
Subtraction Property of Inequality g + 12 - ge 70 -
Simplify 8g ge
Division Property of Inequality 8g _
ge 58 _
Simplify g ge
Check your answer
Since g ge 725 check a larger number 8(8 + 150) ge 70
Sergio must spend at least on each gift ge 70
Reflect
3 Discussion Why is the first step in solving the inequality to use the Distributive Property instead of working inside the parentheses
Your Turn
4 Zachary is planning to send a video game to each of his two brothers If he buys the same game for both brothers and pays $475 to ship each game how much can he spend on each game without spending more than $100 Write and solve an inequality for this situation
Solve each inequality
5 4 _ 3 (6x + 9) lt 4 6 -2 ( 1 _ 4 x + 2 ) ge 5
Module 2 75 Lesson 4
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oug
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Explain 2 Creating and Solving Inequalities with Variables on Both Sides
Some inequalities have variable terms on both sides of the inequality symbol You can solve these inequalities the same way you solved equations with variables on both sides Use the properties of inequality to collect all the variable terms on one side and all the constant terms on the other side
Example 2
A The Daily Info charges a fee of $650 plus $80 per week to run an ad The Peoplersquos Paper charges $145 per week For how many weeks must an ad run for the total cost at the Daily Info to be less expensive than the cost at the Peoplersquos Paper Let w be the number of weeks the ad runs in the paper
Write an inequality to represent the situation 650 + 80w lt 145w
Subtraction Property of Inequality 650 + 80w - 80w lt 145w - 80w
Simplify 650 lt 65w
Division Property of Inequality 650 _ 65 lt 65w _ 65
Simplify 10 lt w
The total cost at the Daily Info is less than the cost at the Peoplersquos Paper if the ad runs for more than 10 weeks
B The Home Cleaning Company charges $312 to power-wash the siding of a house plus $12 for each window Power Clean charges $36 per window and the price includes power-washing the siding How many windows must a house have to make the total cost from The Home Cleaning Company less expensive than Power Clean Let w be the number of windows
Write an inequality to represent the situation +12w lt 36w
Subtraction Property of Inequality 312 + 12w - lt 36w -
Simplify 312 lt
Division Property of Inequality 312 _ lt 24w _
Simplify lt w
A house must have more than 13 windows for The Home Cleaning Company to be less expensive than Power Clean
Reflect
7 How would the final inequality change if you divided by ndash24 in the next to last step
Your Turn
8 The school band will sell pizzas to raise money for new uniforms The supplier charges $100 plus $4 per pizza The band members sell the pizzas for $7 each Write and solve an inequality to find how many pizzas the band members will have to sell to make a profit
Module 2 76 Lesson 4
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Elaborate
9 Which inequality symbol would you use to represent the following words or phrases Can you come up with more examples
a at most b farther than c younger than d up to
10 Discussion How are the steps to solving an inequality similar to those for solving an equation How are they different
11 Essential Question Check-In How can you write an inequality that represents a real-world situation
Write an inequality that represents the description and then solve
1 Max has more than 5 carrots (number of carrots Max has = c)
2 Brigitte is shorter than 5 feet (Brigittersquos height = h)
3 Twice a number (x) is less than 10 4 Six more than five times a number (x) is at least twenty-one
5 Dave has $15 to spend on an $8 book and two birthday cards (c) for his friends How much can he spend on each card if he buys the same card for each friend
6 Toni can carry up to 18 lb in her backpack Her lunch weighs 1 lb her gym clothes weigh 2 lb and her books (b) weigh 3 lb each How many books can she carry in her backpack
Evaluate Homework and Practice
bull Online Homeworkbull Hints and Helpbull Extra Practice
Module 2 77 Lesson 4
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Solve each inequality
7 3 (x - 2) gt -3 8 5 + 5 (x + 4) le 20 9 3 + 1 _ 2 (3 - x) lt -7
10 3 (x + 6) - 2 (x + 2) ge 10 11 5 (3 - x) -4 (2 - 3x) gt 2 12 1 _ 2 (4x - 2) - 2 _ 3 (6x + 9) le 4
13 x + 1 gt -5 (7 - 2x) 14 5 _ 3 (6x + 3) le 2x - 7
15 2x le - 2 __ 3 (4x + 4) 16 1 __ 2 (-2x - 10) gt 3 (4 - 6x)
17 -5 - 3x ge 2 (10 + 2x) + 3 18 -3 (9x + 20) ge 15x - 20
19 8 ( 1 _ 4 x - 3) + 24 lt 4 ( x + 5 ) 20 6x - 2 (x + 2) gt 2 - 3 (x + 3)
Module 2 78 Lesson 4
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21 Physics A crane cable can support a maximum load of 15000 kg If a bucket has a mass of 2000 kg and gravel has a mass of 1500 kg for every cubic meter how many cubic meters of gravel (g) can be safely lifted by the crane
22 Find the solution set of each inequality below and then determine which inequalities have the same solution set as 1 _ 3 ( -5x - 3 ) lt 14
a 1 _ 3 (5x + 3) gt -14 b 2 _ 5 (10x + 20) gt 44
c - 2 _ 5 (10x + 20) lt -44 d - 1 _ 3 (5x + 3) lt 14
e 2 _ 5 (10x - 20) gt -44 f 1 _ 3 (5x + 3) lt -14
HOT Focus on Higher Order Thinking
23 Explain the Error Sven is trying to find the maximum amount of time he can spend practicing the five scales of piano music he is supposed to be working on He has 60 minutes to practice piano and would like to spend at least 35 minutes playing songs instead of practicing scales So Sven sets up the following inequality where t is the number of minutes he spends on each scale and solves it
60 - 5t le 35-5t le -25
t ge 5
Sven has concluded that he should spend 5 minutes or more on each scale Is this correct If not what mistake did he make Then solve for the correct answer
Module 2 79 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
24 Critical Thinking Anika wants to determine the maximum number of tulip bulbs (t) she can purchase if each bulb costs $150 She will also need to purchase separate pots for each bulb at $125 each and a bag of potting soil for $1000 Set up an inequality to determine how many tulip bulbs Anika can purchase without spending more than $2000 and solve it Can Anika buy exactly enough bulbs and pots to spend the full $2000 Explain Can you think of a better inequality to describe the answer
25 Geometry The area of the triangle shown is no more than 10 square inches
a Write an inequality that can be used to find x
b Solve the inequality from part a c What is the maximum height of the triangle
Lesson Performance TaskWhen planning an airplane route the trip planner must be careful to consider the range the aircraft can travel and the availability of airports to stop and refuel
A large commercial jet airplane burns approximately 5 gallons of fuel per mile flown plus about 8500 gallons of fuel per trip to reach cruising altitude With a useable fuel capacity of 50000 gallons (there is additional fuel reserved for emergencies) describe the acceptable distance for which an airline could establish a non-stop flight
For flights originating from Chicago determine which cities could be safely reached by a non-stop flight
City Distance from Chicago (miles)
Bangalore India 8530
Jakarta Indonesia 9810
Johannesburg South Africa 8680
Moscow Russia 4970
Paris France 4130
Perth Australia 10970
Tokyo Japan 6300
copy H
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its copySarych
eva O
lesiaShutterstock
(2x - 3) in
4 in
Module 2 80 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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Har
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Name Class Date
Resource Locker
Explore Truth Tables and Compound StatementsA compound statement is formed by combining two or more simple statements A compound statement can be true or false A compound statement involving AND is true when both simple statements are true A compound statement involving OR is true when either one simple statement or both are true
A Complete the truth table
P QP
True or FalseQ
True or FalseP AND Q
True or False
A dog is a mammal Red is a color
A dog is a mammal Red is not a color
A dog is a fish Red is a color
A dog is a fish Red is not a color
B P AND Q is true when
C Complete the truth table
P QP
True or FalseQ
True or FalseP OR Q
True or False
1 is an odd number 2 is an even number
1 is an odd number 2 is an odd number
1 is an even number 2 is an even number
1 is an even number 2 is an odd number
D P OR Q is true when
Reflect
1 Give two simple statements P and Q for which P AND Q is false and P OR Q is true
Module 2 81 Lesson 5
25 Creating and Solving Compound Inequalities
Essential Question How can you solve a compound inequality and graph the solution set
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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Explain 1 Solving Compound Inequalities Involving ANDCombining two or more simple inequalities forms a compound inequality The graph of a compound inequality involving AND is the intersection or the overlapping region of the simple inequality graphs
Compound Inequalities AND
Words Algebra Graph
All real numbers greater than 2AND less than 6
x gt 2 AND x lt 62 lt x lt 6
All real numbers greater than or equal to 2 AND less than or equal to 6
x ge 2 AND x le 62 le x le 6
Example 1 Solve each compound inequality and graph the solutions
A 4 le x + 2 le 8
4 le x + 2 AND x + 2 le 8 Write the compound inequality using AND
4 - 2 le x + 2 - 2 x + 2 - 2 le 8 - 2 Subtract 2 from both sides of each simple inequality
2 le x x le 6 Simplify
Graph 2 le x
Graph x le 6
Graph the intersection by finding where the two graphs overlap
B -5 le 2x + 3 lt 9
-5 - le 2x + 3 - lt 9 - Subtract from each part of the inequality
le 2x lt Simplify
-8 _ le 2x _ lt 6 _ Divide each part of the inequality by
le x lt Simplify
Graph -4 le x
Graph x lt 3
Graph the intersection by finding where the two graphs overlap -1 0 1 2 3 4 5-5-4 -3 -2
0 2 4 6 8 10 12-8-6-4 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 82 Lesson 5
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pan
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Reflect
2 Discussion Explain why 2 le x le 6 can be considered the short method for writing the AND compound inequality x ge 2 AND x le 6
YourTurn
Solve each compound inequality and graph the solutions
3 -2 lt x - 3 lt 5
4 -10 lt 3x + 2 le 8
Explain 2 Solving Compound Inequalities Involving ORThe graph of a compound inequality involving OR is the union or the combined region of the simple inequality graphs
Compound Inequalities OR
Words Algebra Graph
All real numbers less than 2OR greater than 6
x lt 2 OR x gt 6
All real numbers less than or equal to 2OR greater than or equal to 6
x le 2 OR x ge 6
-1 0 1 2 3 4 5-5-4 -3 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 83 Lesson 5
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Example 2 Solve each compound inequality and graph the solutions
A -4 + x gt 1 OR -4 + x lt -3
-4 + x gt 1 OR -4 + x lt -3 Write the compound inequality using OR
-4 + 4 + x gt 1 + 4 -4 + 4 + x lt -3 + 4 Add 4 to both sides of each simple inequality
x gt 5 x lt 1 Simplify
Graph x gt 5
Graph x lt 1
Graph the union by combining the graphs
B 2x le 6 OR 3x gt 12
2x le 6 OR 3x gt 12 Write the compound inequality using OR
2x _ le 6 _ OR 3x _ gt 12 _ Divide the first simple inequality by
x le OR x gt
Graph x le 3
Graph x gt 4
Graph the union by combining the graphs
Reflect
5 Critical Thinking What kind of compound inequality has no solution
Divide the second simple inequality by
Simplify
0 1 2 3 4 5 6-4 -3 -2 -1
-0 1 2 3 4 5 6-4 -3 -2 -1
Module 2 84 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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cour
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Com
pan
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Your Turn
Solve each compound inequality and graph the solutions
6 x - 5 ge -2 OR x -5 le -6
7 4x -1 lt 15 OR 8x ge 48
Explain 3 Creating Compound Inequalities From GraphsGiven a number line graph with a solution set graphed you can create a compound inequality to fit the graph
Example 3 Write the compound inequality shown by each graph
A
The shaded portion of the graph is not between two values so the compound inequality involves OR
On the left the graph shows an arrow pointing left from -1 and a solid circle so use le
The inequality is x le -1
On the right the graph shows an arrow pointing right from 7 and a solid circle so use ge
The inequality is x ge 7
The compound inequality is x le -1 OR x ge 7
B
The graph is shaded between the values and so the compound inequality involves AND
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The compound inequality is
-1 0 1 2 3 4 5-5-4 -3 -2
4 5 6 7 8 9 100 1 2 3
2 3 4 5 6 7 8-2 -1 0 1
10 2 3 4 5 6 7 8 9-1
Module 2 85 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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Reflect
8 What is a short method to write the compound inequality x ge 0 AND x lt 6
Your Turn
Write the compound inequality shown by each graph
9
10
Explain 4 Expressing Acceptable Levels with Compound Inequalities
You can express quality-controls levels in real-world problems using compound inequalities
Example 4 Write a compound inequality to represent the indicated quality-control level and graph the solutions
A The recommended pH level for swimming pool water is between 72 and 76 inclusive
Let p be the pH level of swimming pool water
72 is less than or equal to pH level is less than or equal to 76
72 le p le 76
The compound inequality is 72 le p le 76
Graph the solutions
0-10 -8-9 -7-6 -5-4 -3 -2 -1
71 72 73 74 75 76 77 78 79 8070
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 86 Lesson 5
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B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
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bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
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Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
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Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
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bik
erid
erlo
nd
onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
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The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
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What are the factors of each term is the only factor of the
term and and are the factors of the term
Do both terms have coefficients Explain
What are the coefficients
What does the expression 15 - 02b mean in the given situation
Reflect
1 Sally identified the terms of the expression 9a + 4b - 18 as 9a 4b and 18 Explain her error
2 What is the coefficient of b in the expression b + 10 Explain
Explain 1 Interpreting Algebraic Expressions in Context In many cases real-world situations and algebraic expressions can be related The coefficients variables and operations represent the given real-world context
Interpret the algebraic expression corresponding to the given context
Example 1
Curtis is buying supplies for his school He buys p packages of crayons at $149 per package and q packages of markers at $349 per package What does the expression 149p + 349q represent
Interpret the meaning of the term 149p What does the coefficient 149 represent
The term 149p represents the cost of p packages of crayons The coefficient represents the cost of one package of crayons $149
Interpret the meaning of the term 349q What does the coefficient 349 represent
The term 349q represents the cost of q packages of markers The coefficient represents the cost of one package of markers $349
Interpret the meaning of the entire expression
The expression 149p + 349q represents the total cost of p packages of crayons and q packages of markers
Jill is buying ink jet paper and laser jet paper for her business She buys 8 more packages of ink jet paper than p packages of laser jet paper Ink jet paper costs $695 per package and laser jet paper costs $8 per package What does the expression 8p + 695(p + 8) represent
Interpret the meaning of the first term 8p What does the coefficient 8 represent
The term 8p represents the cost of The coefficient represents $8
Interpret the meaning of the second expression 695(p + 8) What do the factors 695 and (p + 8) represent
Module 2 46 Lesson 1
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oug
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pan
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The term 695(p + 8) represents 695 represents the cost of (p + 8) represents that Jill bought
Interpret the expression 8p + 695(p + 8)
The expression represents that Jill bought
Your Turn
Interpret the algebraic expression corresponding to the given context
3 George is buying watermelons and pineapples to make fruit salad He buys w watermelons at $449 each and p pineapples at $5 each What does the expression 449w + 5p represent
4 Sandi buys 5 fewer packages of pencils than p packages of pens Pencils costs $225 per package and pens costs $3 per package What does the expression 3p + 225(p - 5) represent
Explain 2 Comparing Algebraic ExpressionsGiven two algebraic expressions involving two variables we can compare whether one is greater or less than the other We can denote the inequality between the expressions by using lt or gt symbols If the expressions are the same or equivalent expressions we denote this equality by using =
Suppose x and y give the populations of two different cities where x gt y Compare the expressions and tell which of the given pair is greater
Example 1
x + y and 2x
The expression 2x is greater
bull Putting the lesser population y together with the greater population x gives a population that is less than double the greater population
x _ y and y _ x
Since x gt y x _ y will be than 1 and y _ x will be than 1
So x _ y y _ x
Your Turn
Suppose x and y give the populations of two different cities where x gt y and y gt 0 Compare the expressions and tell which of the given pair is greater
5 x _ x + y and x + y
_ x 6 2(x + y) and (x + y)2
Module 2 47 Lesson 1
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oug
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Explain 3 Modeling Expressions in ContextThe table shows some words and phrases associated with the four basic arithmetic operations These words and phrases can help you translate a real-world situation into an algebraic expression
Operation Words Examples
Addition the sum of added to plus more than increased by total altogether and
1 A number increased by 22 The sum of n and 23 n + 2
Subtraction less than minus subtracted from the difference of take away taken from reduced by
1 The difference of a number and 22 2 less than a number3 n - 2
Multiplication times multiplied by the product of percent of
1 The product of 06 and a number2 60 of a number3 06n
Division divided by division of quotient of divided into ratio of
1 The quotient of a number and 52 A number divided by 53 n divide 5 or n __ 5
Example 3 Write an algebraic expression to model the given context Give your answer in simplest form
the price of an item plus 6 sales tax
Price of an item + 6 sales tax
p + 006p
The algebraic expression is p + 006p or 106p
the price of a car plus 85 sales tax
The price of a car +
+
The algebraic expression is
or
Reflect
7 Use the Distributive Property to show why p + 006p = 106p
8 What could the expression 3(p + 006p) represent Explain
Your Turn
Write an algebraic expression to model the given context Give your answer in simplest form
9 the number of gallons of water in a tank that already has 300 gallons in it after being filled at 35 gallons per minute for m minutes
10 the original price p of an item less a discount of 15
Module 2 48 Lesson 1
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Elaborate
11 When given an algebraic expression involving subtraction why is it best to rewrite the expression using addition before identifying the terms
12 How do you interpret algebraic expressions in terms of their context
13 How do you simplify algebraic expressions
14 Essential Question Check In How do you write algebraic expressions to model quantities
bull Online Homeworkbull Hints and Helpbull Extra Practice
Evaluate Homework and PracticeIdentify the terms and the coefficients of the expression
1 -20 + 5p - 7z 2 8x - 20y - 10
Identify the factors of the terms of the expression
3 5 + 6a + 11b 4 13m - 2n
5 Erin is buying produce at a store She buys c cucumbers at $099 each and a apples at $079 each What does the expression 099c + 079a represent
6 The number of bees that visit a plant is 500 times the number of years the plant is alive where t represents the number of years the plant is alive What does the expression 500t represent
Evaluate Homework and Practice
Module 2 49 Lesson 1
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oug
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Leonard
LenzC
orbis
7 Lorenzo buys 3 shirts at s dollars apiece and 2 pairs of pants at p dollars a pair What does the expression 3s + 2p represent
8 If a car travels at a speed of 25 mih for t hours then travels 45 mih for m hours what does the expression 25t + 45m represent
9 The price of a sandwich is $150 more than the price of a smoothie which is d dollars What does the expression d + 15 represent
10 A bicyclist travels 1 mile in 5 minutes If m represents minutes what does the expression m __ 5 represent
11 What are the factors of the expression (y - 2)(x + 3)
12 Explain the Error A student wrote that there are two terms in the expression 3p - (7 - 4q) Explain the studentrsquos error
13 Yolanda is buying supplies for school She buys n packages of pencils at $140 per package and m pads of paper at $120 each What does each term in the expression 14n + 12m represent What does the entire expression represent
14 Chris buys p pairs of pants and 4 more shirts than pairs of pants Shirts cost $18 each and pair of pants cost $25 each What does each term in the expression 25p + 18(p + 4) represent What does the entire expression represent
Module 2 50 Lesson 1
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ssie
W
alke
rLi
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In Im
ages
Cor
bis
Suppose a and b give the populations of two states where a gt b Compare the expressions and tell which of the given pair is greater or if the expressions are equal
15 b _ a + b
and 05
16 a + 13c and b + 13c where c is the population of a third state
17 a - b _ 2 and a - b _ 2
18 a + b and 2b
19 5(a + b) and (a + b)5
Write an algebraic expression to model the given context Give your answer in simplest form
20 the price s of a pair of shoes plus 5 sales tax 21 the original price p of an item less a discount of 20
22 the price h of a recently bought house plus 10 property tax
23 the principal amount P originally deposited in a bank account plus 03 interest
Module 2 51 Lesson 1
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24 Match each statement with the algebraic expression that models it
A the price of a winter coat and a 20 discount x + 002x = 102x
B the base salary of an employee and a 2 salary increase x - 020x = 080x
C the cost of groceries and a 2 discount with coupons x + 020x = 120x
D the number of students attending school last year and a 20 increase from last year x - 002x = 098x
HOT Focus on Higher Order Thinking
25 Critique Reasoning A student is given the rectangle and the square shown The student states that the two figures have the same perimeter Is the student correct Explain your reasoning
26 Multi-Step Yon buys tickets to a concert for himself and a friend There is a tax of 6 on the price of the tickets and an additional booking fee of $20 for the transaction Write an algebraic expression to represent the price per person Simplify the expression if possible
x + 2
x + 2x
x + 4
Module 2 52 Lesson 1
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27 Persevere in Problem Solving Jerry is planting white daisies and red tulips in his garden and he wants to choose a pattern in which the tulips surround the daisies He uses tiles to generate patterns starting with two rows of three daisies He surrounds these daisies with a border of tulips The design continues as shown
a Jerry writes the expression 8(b - 1) + 10 for the number of tulips in each border wherein b is the border number and b ge 1 Explain why Jerryrsquos expression is correct
b Elaine wants to start with two rows of four daisies Her reasoning is that Jerry started with two rows of three daisies and his expression was 8(b - 1) + 10 so if she starts with two rows of four daisies her expression will be 10(b - 1) + 10 Is Elainersquos statement correct Explain
Border 1 Border 2 Border 3
Module 2 53 Lesson 1
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Lesson Performance Task
Becky and Michele are both shopping for a new car at two different dealerships Dealership A is offering $500 cash back on any purchase while Dealership B is offering $1000 cash back The tax rate is 5 at Dealership A but 8 at Dealership B Becky wants to buy a car that is $15000 and Michele is planning to buy a car that costs $20000 Use algebraic expressions to help you answer the following questions
a At which dealership will Becky get the better deal How much does she save
b At which dealership will Michele get the better deal How much does she save
c What generalization can you make that would help any shopper know which dealership has the better deal [Hint At what price point would the two deals be equal]
copy H
oug
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Tom G
rillC
orbis
Module 2 54 Lesson 1
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Name Class Date
Resource Locker
Explore Creating Equations from Verbal Descriptions
You can use what you know about writing algebraic expressions to write an equation that represents a real-world situation
Suppose Cory and his friend Walter go to a movie Each of their tickets costs the same amount and they share a frozen yogurt that costs $550 The total amount they spend is $1990 How can you write an equation that describes the situation
A Identify the important information
The word tells you that the relationship describes an equation
The word total tells you that the operation involved in the relationship is
What numerical information do you have
What is the unknown quantity
B Write a verbal description
Choose a name for the variable In this case use c for
The verbal description is Twice the cost of plus the cost
of equals
C To write an equation write a numerical or expression for each quantity
and insert an equal sign in the appropriate place An equation is
Reflect
1 How can you use a verbal model to write an equation for the situation described
Module 2 55 Lesson 2
22 Creating and Solving EquationsEssential Question How do you use an equation to model and solve a real-world problem
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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age C
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igital
Vision
Getty Im
ages
2 Could you write a different equation to describe the situation Explain your reasoning
Explain 1 Creating and Solving Equations Involving the Distributive Property
When you create an equation to model a real-world problem your equation may involve the Distributive Property When you solve a real-world problem you should always check that your answer makes sense
Example 1 Write and solve an equation to solve each problem
A Aaron and Alice are bowling Alicersquos score is twice the difference of Aaronrsquos score and 5 The sum of their scores is 320 Find each studentrsquos bowling score
Write a verbal description of the basic situation
The sum of Aaronrsquos score and Alicersquos score is 320
Choose a variable for the unknown quantity and write an equation to model the detailed situation
Let a represent Aaronrsquos score Then 2 (a - 5) represents Alicersquos score
a + 2 (a - 5) = 320
Solve the equation for a
a + 2 (a - 5) = 320
a + 2a - 10 = 320 Distributive Property
3a - 10 = 320
3a - 10 + 10 = 320 + 10 Addition Property of Equality
3a = 330
3a _ 3 = 330 _ 3 Division Property of Equality
a = 110
So Aaronrsquos score is 110 and Alicersquos score is 2 (a - 5) = 2 (110 - 5) = 2 (105) = 210
Check that the answer makes sense
110 + 210 = 320 so the answer makes sense
B Mari Carlos and Amanda collect stamps Carlos has five more stamps than Mari and Amanda has three times as many stamps as Carlos Altogether they have 100 stamps Find the number of stamps each person has
Write a verbal description of the basic situation
Module 2 56 Lesson 2
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pan
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Choose a variable for the unknown quantity and write an equation to model the detailed situation
Let s represent the number of stamps Mari has Then Carlos has stamps
and Amanda has stamps
s + + 3 ( ) =
Solve the equation for s
s + + 3 ( ) =
s + s + 5 + 3s + = Distributive Property
+ = Combine like terms
s = Subtraction Property of Equality
s = Division Property of Equality
So Mari has stamps Carlos has stamps and Amanda
has stamps
Check that the answer makes sense
+ + = the answer makes sense
=
Reflect
3 Would a fractional answer make sense in this situation
4 Discussion What might it mean if a check revealed that the answer to a real-world problem did not make sense
Module 2 57 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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pany
Your Turn
Write and solve an equation to solve the problem
5 A rectangular garden is fenced on all sides with 256 feet of fencing The garden is 8 feet longer than it is wide Find the length and width of the garden
Explain 2 Creating and Solving Equations with Variables on Both Sides
In some equations variables appear on both sides You can use the properties of equality to collect the variable terms so that they all appear on one side of the equation
Example 2 Write and solve an equation to solve each problem
A Janine has job offers at two companies One company offers a starting salary of $28000 with a raise of $3000 each year The other company offers a starting salary of $36000 with a raise of $2000 each year In how many years would Janinersquos salary be the same with both companies What will the salary be
Write a verbal description of the basic situation
Let n represent the number of years it takes for the salaries to be equal
Base Salary A plus $3000 per year raise = Base Salary B + $2000 per year raise
28000 + 3000n = 36000 + 2000n
28000 + 3000n - 2000n = 36000 + 2000n - 2000n Subtraction Property of Equality
28000 + 1000n = 36000 Combine like terms
28000 + 1000n - 28000 = 36000 - 28000 Subtraction Property of Equality
1000n = 8000 1000n _ 1000 = 8000 _ 1000 Division Property of Equality
n = 8
28000 + 3000 (8) = 36000 + 2000 (8)
52000 = 52000
In 8 years the salaries offered by both companies will be $52000
(w + 8) feet
w feet
Module 2 58 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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oug
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Mif
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cour
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lishi
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Com
pan
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B One moving company charges $800 plus $16 per hour Another moving company charges $720 plus $21 per hour At what number of hours will the charge by both companies be the same What is the charge
Write a verbal description of the basic situation Let t represent the number of hours that the move takes
Moving Charge A plus $16 per hour = Moving Charge B plus $21 per hour
800 + t = 720 + t
800 + t - t = 720 + t - t Subtraction Property of Equality
800 = 720 + t
800 - 720 = 720 + t - 720 Subtraction Property of Equality
= t
_ = t _
Division Property of Equality
t =
The charges are the same for a job that takes hours
Substitute the value 16 in the original equation
800 + 16t = 720 + 21t
800 + 16 ( ) = 720 + 21 ( ) 800 + = 720 +
=
After hours the moving charge for both companies will be
Reflect
6 Suppose you collected the variable terms on the other side of the equal sign to solve the equation Would that affect the solution
Module 2 59 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
arcourt Publishin
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pany
Your Turn
Write and solve an equation to solve each problem7 Claire bought just enough fencing to enclose either a
rectangular garden or a triangular garden as shown The two gardens have the same perimeter How many feet of fencing did she buy
8 A veterinarian is changing the diets of two animals Simba and Cuddles Simba currently consumes 1200 Calories per day That number will increase by 100 Calories each day Cuddles currently consumes 3230 Calories a day That number will decrease by 190 Calories each day The patterns will continue until both animals are consuming the same number of Calories each day In how many days will that be How many Calories will each animal be consuming each day then
Explain 3 Constructing Equations from an Organized TableYou can use a table to organize information and see relationships
Example 3 Construct and solve an equation to solve the problem
Kim works 4 hours more each day than Jill does and Jack works 2 hours less each day than Jill does Over 2 days the number of hours Kim works is equal to the difference of 4 times the number of hours Jack works and the number of hours Jill works How many hours does each person work each day
Analyze Information
Identify the important information
bull Kim works hours more per day than Jill does
bull Jack works hours less per day than Jill does
Formulate a Plan
Make a table using the information given Let x be the number of hours Jill works in one day
Hours Worked Per Day Hours Worked Over 2 Days
Kim
Jill
Jack
Over 2 days the number of hours Kim works is equal to the difference of 4 times the number of hours Jack works and the number of hours Jill works
(3x - 3)(x - 3)
(2x - 1) (2x - 1)
2x
Module 2 60 Lesson 2
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oug
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Mif
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cour
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pan
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Solve
2 (x + 4) = 4 2 (x - 2) - 2x
2 (x + 4) = (x - 2) - 2x Simplify
2x + = 8x - - 2x Distributive Property
2x + 8 = x - 16
2x + 8 + = 6x - 16 + Addition Property of Equality
2x + = 6x
2x + 24 - x = 6x - x Subtraction Property of Equality
24 = x
24 _ = x _ Division Property of Equality
= x
Jill works hours per day Kim works hours per day and Jack works
hours per day
Justify and Evaluate
Substitute x = 6 into the original equation
2 (6 + 4) = 4 2 (6 - 2) - 2x
2 ( ) = 8 ( ) - 2 ( ) =
Your Turn
Write and solve an equation to solve the problem
9 Lisa is 10 centimeters taller than her friend Ian Ian is 14 centimeters taller than Jim Every month their heights increase by 2 centimeters In 7 months the sum of Ianrsquos and Jimrsquos heights will be 170 centimeters more than Lisarsquos height How tall is Ian now
Height now Height after 7 months
Module 2 61 Lesson 2
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Elaborate
10 How can you use properties to solve equations with variables on both sides
11 How is a table helpful when constructing equations
12 When solving a real-world problem to find a personrsquos age would a negative solution make sense Explain
13 Essential Question Check-In How do you write an equation to represent a real-world situation
bull Online Homeworkbull Hints and Helpbull Extra Practice
Write an equation for each description
1 The sum of 14 and a number is equal to 17 2 A number increased by 10 is 114
3 The difference between a number and 12 is 20 4 Ten times the sum of half a number and 6 is 8
5 Two-thirds a number plus 4 is 7 6 Tanmayi wants to raise $175 for a school fundraiser She has raised $120 so far How much more does she need to reach her goal
7 Hector is visiting a cousin who lives 350 miles away He has driven 90 miles How many more miles does he need to drive to reach his cousinrsquos home
8 The length of a rectangle is twice its width The perimeter of the rectangle is 126 feet
Evaluate Homework and Practice
Module 2 62 Lesson 2
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Pete
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imS
hutt
erst
ock
Write and solve an equation for each situation
9 In one baseball season Peter hit twice the difference of the number of home runs Alice hit and 6 Altogether they hit 18 home runs How many home runs did each player hit that season
10 The perimeter of a parallelogram is 72 meters The width of the parallelogram is 4 meters less than its length Find the length and the width of the parallelogram
11 One month Ruby worked 6 hours more than Isaac and Svetlana worked 4 times as many hours as Ruby Together they worked 126 hours Find the number of hours each person worked
12 In one day Annie traveled 5 times the sum of the number of hours Brian traveled and 2 Together they traveled 20 hours Find the number of hours each person traveled
13 Xian and his cousin Kai both collect stamps Xian has 56 stamps and Kai has 80 stamps The boys recently joined different stamp-collecting clubs Xianrsquos club will send him 12 new stamps per month Kairsquos club will send him 8 new stamps per month After how many months will Xian and Kai have the same number of stamps How many stamps will each have
14 Kenya plans to make a down payment plus monthly payments in order to buy a motorcycle At one dealer she would pay $2500 down and $150 each month At another dealer she would pay $3000 down and $125 each month After how many months would the total amount paid be the same for both dealers What would that amount be
ℓ meters
(ℓ - 4) meters
Module 2 63 Lesson 2
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15 Community Gym charges a $50 membership fee and a $55 monthly fee Workout Gym charges a $200 membership fee and a $45 monthly fee After how many months will the total amount of money paid to both gyms be the same What will the amount be
16 Tina is saving to buy a notebook computer She has two options The first option is to put $200 away initially and save $10 every month The second option is to put $100 away initially and save $30 every month After how many months would Tina save the same amount using either option How much would she save with either option
Use the table to answer each question
Starting Salary Yearly Salary Increase
Company A $24000 $3000
Company B $30000 $2400
Company C $36000 $2000
17 After how many years are the salaries offered by Company A and Company B the same
18 After how many years are the salaries offered by Company B and Company C the same
19 Paul started work at Company B ten years ago at the salary shown in the table At the same time Sharla started at Company C at the salary shown in the table Who earned more during the last year How much more
20 Georgersquos page contains twice as many typed words as Billrsquos page and Billrsquos page contains 50 fewer words than Charliersquos page If each person can type 60 words per minute after one minute the difference between twice the number of words on Billrsquos page and the number of words on Charliersquos page is 210 How many words did Billrsquos page contain initially Use a table to organize the information
Initial number of words
Total number of words after one minute
Module 2 64 Lesson 2
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pan
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21 Geometry Sammie bought just enough fencing to border either a rectangular plot or a square plot as shown The perimeters of the plots are the same How many meters of fencing did she buy
HOT Focus on Higher Order Thinking
22 Justify Reasoning Suppose you want to solve the equation 2a + b = 2a where a and b are nonzero real numbers Describe the solution to this equation Justify your description
23 Multi-step A patio in the shape of a rectangle is fenced on all sides with 134 feet of fencing The patio is 5 feet less wide than it is long
a What information can be used to solve the problem How can you find the information
b Describe how to find the area of the patio What is the area of the patio
24 Explain the Error Kevin and Brittany write an equation to represent the following relationship and both students solve their equation Who found the correct equation and solution Why is the other person incorrect
5 times the difference of a number and 20 is the same as half the sum of 4 more than 4 times a number
Kevin Brittany
5 (x - 20) = 1 _ 2 (4x + 4) 5 (20 + x) = 1 _ 2 (4x + 4)
5x - 100 = 2x + 2 100 - 5x = 2x + 2
3x - 100 = 2 100 - 7x = 2
3x = 102 -7x = -98
x = 34 x = 14
(3x + 2) meters
(x + 2) meters
(x + 2) meters
(x - 1) meters
ℓ feet
(ℓ - 5) feet
Module 2 65 Lesson 2
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25 What If Alexa and Zack are solving the following problem
The number of miles on Car A is 50 miles more than the number of miles on Car B and the number of miles on Car B is 30 miles more than the number of miles on Car C All the cars travel 50 miles in 1 hour After 1 hour twice the number of miles on Car A is 70 miles less than 3 times the number of miles on Car C How many miles were there on Car B initially
Alexa assumes there are m miles on Car B Zack assumes there are m miles on Car C Will Zackrsquos answer be the same as Alexarsquos answer Explain
Lesson Performance Task
Stacy Oliver and Jivesh each plan to put a certain amount of money into their savings accounts that earn simple interest of 6 per year Stacy puts $550 more than Jivesh and Oliver puts in 2 times as much as Jivesh After a year the amount in Stacyrsquos account is 2 times the sum of $212 and the amount in Oliverrsquos account How much does each person initially put into his or her account Who had the most money in his or her account after a year Who had the least Explain
Zackrsquos Table Initial Miles
Miles after One Hour
Alexarsquos Table Initial Miles
Miles after One Hour
Amount in Account Initially Amount in Account after One Year
Module 2 66 Lesson 2
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oug
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Name Class Date
Resource Locker
Explore Rearranging Mathematical FormulasLiteral Equations are equations that contain two or more variables There are many literal equations in the form of math science and engineering formulas These formulas may seem like they can only be solved for the variable that is isolated on one side of the formula By using inverse operations and the properties of equality a formula can be rearranged so any variable in the formula can be isolated It is no different than how equations are solved by using inverse operations and the properties of equality
How can you solve the equation 42 = 6x
A42 _ = 6x _ What is the reason for dividing
Why divide by
= x By rearranging the equation x was isolated and the solution was found
The mathematical formula for the volume of a rectangular prism B = Vh or V = ℓwh is a literal equation V represents volume ℓ represents length w represents width and h represents height Using inverse operations the formula can be rearranged to solve for any one of the variables that might be unknown Like solving for x a formula can be rearranged to isolate a variable
B In the formula V = ℓwh the variable h needs to be isolated
The operation of is used in the formula The inverse
operation should be used
to isolate
C V _____ = ℓwh _____
V _ =
The formula rearranged in this way can easily produce the height of the rectangular prism when the volume length and width are known
Reflect
1 Using the formula for a rectangular prism rewrite the formula to solve for ℓ
ℓw
h
Module 2 67 Lesson 3
23 Solving for a VariableEssential Question How do you rewrite formulas and literal equations
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Photo
grap
hyAurora Ph
otosCorb
is
Explain 1 Rearranging Scientific FormulasUse inverse operations to isolate the unknown variable in a scientific formula
The formula for density is D = m __ V Lead has a very high density of 11340 kg m 3 Plastic foam has a very low density of 75 kg m 3 The formula for density can be rearranged to solve for V volume or m mass
Example 1
A A sinker on a fishing line is made of lead and has a volume of 0000015 m 3 What is the mass of the sinker
The density formula can be rearranged to isolate m the mass The values for volume and density can then be substituted into the formula to find the mass
D = m _ V
DV = ( m _ V ) V DV = m
(11340 kg m 3 ) (0000015 m 3 ) = m
017 kg asymp m
B The design for a life preserver requires 03 kilogram of plastic foam to provide proper buoyancy What is the volume of the plastic foam required
Rearrange the density formula to isolate V
D = m _ V
(D) V = m _ V
DV =
DV _ = m _
V =
Now substitute the given values
V = _
V = m 3
Your Turn
2 For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Determine the altitude in feet when t is -275 ∘F and g is 60 ∘F
Module 2 68 Lesson 3
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Explain 2 Rearranging Literal EquationsUsing inverse operations to rearrange literal equations can be applied to any formula The interest formula I = prt is another example of a literal equation In the formula I represents interest p the principal or the initial amount to which interest will be applied r the rate at which interest will be paid and t is the time in years
Example 2
A Find the number of years used in the calculation of a $1000 loan at an interest rate of 5 with interest totaling $600
Solve the formula for t
I = prt
I _ pr = prt
_ pr
I _ pr = t
Substitute the given values Since the interest rate is 5 r = 005$600 __
$1000 middot 005 = t
12 = t
So the length of time for the loan is 12 years
B Determine the interest rate for a $2000 loan that will be paid off in 4 years with interest totaling $640 In order to find the interest rate solve the formula for r
I = prt
I _ = prt _
_ = r
Now substitute the values and simplify
__
( ) ( ) = r
008 = r
So the interest rate is per year
Your Turn
3 The formula y = mx + b is the slope-intercept form of the equation of a line Solve the equation for m
Module 2 69 Lesson 3
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oug
hton Mifflin H
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pany
bull Online Homeworkbull Hints and Helpbull Extra Practice
Solve for the indicated variable in each mathematical formula
1 C = 2πr for r 2 A = 1 __ 2 bh for b 3 y = mx + b for x
4 A = 1 __ 2 (a + b)h for h 5 V = πr2h for h 6 SA = 2πr2 + 2πrh for h
Solve for the indicated variable in each scientific formula
7 d = rt for t 8 PV = nRT for T
9 A = FV - OV _______ T for OV 10 C = Wtc _ 1000 for W
Evaluate Homework and Practice
Elaborate
4 Discussion What could be a reason for isolating a variable in a literal equation
5 Describe a situation in which a formula could be used more easily if it were rearranged Include the formula in your description
6 Essential Question Check-In How do you isolate a variable
Module 2 70 Lesson 3
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oug
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cour
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pan
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mag
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copyO
cean
C
orb
is
Solve for the indicated variable in each literal equation
11 2p + 5r = q for p 12 -10 = xy + z for x 13 a __ b = c for b
14 h - 4 _ j = k for j 15 x __ 5 - g = a for x 16 5p + 9c = p for c
17 2 __ 5 (z + 1) = y for z 18 g (h + 2 __ 3 ) = 1 for h 19 a(n - 3) + 8 = bn for n
20 Which is a possible way to rewrite the equation y = 3x + 3b to solve for b
A b = y - 3x
_ 3 C b = y - 3
_____ 3x
B b = 3(y - 3x) D b = x(y - 3)
21 Sports To find a baseball pitcherrsquos earned run average (ERA) you can use the formula Ei = 9r in which E represents ERA i represents the number of innings pitched and r represents the number of earned runs allowed Solve the equation for E What is a pitcherrsquos ERA if he allows 5 earned runs in 18 innings pitched
22 Meteorology For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Solve the equation for a If the atmospheric temperature is -655 ∘F and the ground temperature is 57 ∘F what is the altitude
Module 2 71 Lesson 3
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
arcourt Publishin
g Com
pany bull Im
age C
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Rand
y D
uch
aineA
lamy
HOT Focus on Higher Order Thinking
23 Explain the Error A student was asked to use the formula for the perimeter of a rectangle P = 2ℓ + 2w to solve for ℓ The student came up with an answer P - 2w = 2ℓ What error did the student make Explain Then solve for ℓ
24 Multi-Step The formula c = 5p + 215 relates c the total cost in dollars of hosting a birthday party at a skating rink to p the number of people attending If Alliersquos parents are willing to spend $300 for a party how many people can attend
25 Multi-Step The formula for the area of a triangle is A = 1 __ 2 bh in which b represents the length of thebase and h represents the height If a triangle has an area of 192 mm2 and the height is 12 mm what is the measure of the base
Lesson Performance TaskThe following table shows the average low temperatures in Fahrenheit for the city of Boston for several months during the year The formula F = 9 __ 5 C + 32 allows you to determine the temperature in Fahrenheit when given the temperature in Celsius
MonthTemperature in
FahrenheitTemperature in
Celsius
January 22deg
April 41deg
July 65deg
October 47deg
December 28deg
a Use the information given to determine the average low temperatures in Celsius
b Would it ever be possible for the temperature in Celsius to have a greater value than the temperature in Fahrenheit Explain why or why not
Module 2 72 Lesson 3
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
Name Class Date
Resource Locker
copy H
oug
hton
Mif
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Har
cour
t Pub
lishi
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Com
pan
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mag
e cr
edit
s copy
Patr
ick
Lan
eSo
mos
Imag
esC
orb
is
Explore Creating Inequalities from Verbal DescriptionsAn inequality is a statement that compares two expressions that are not strictly equal by using one of the following inequality signs
Symbol Meaning
lt is less than
le is less than or equal to
gt is greater than
ge is greater than or equal to
ne is not equal to
You have probably seen a sign at an amusement park saying something like ldquoYou must be at least 48 inches tall to ride this riderdquo This statement could be written as h ge 48 in where h represents the height of a person allowed to ride
Nora is planning a birthday party for her little sister Colleen Norarsquos budget will allow her to spend no more than $50 for party supplies Eight children including Colleen will attend the party and Nora wants to determine how much she could spend on party favors for each child She will also purchase a cake for $10 Write an inequality that represents the situation and find possible solutions
A First let c represent the cost of a party favor for each child Write an expression for the total cost of the party as a function of c
c +
B Which inequality symbol should be used to represent the phrase ldquono more thanrdquo
C Write the inequality that represents Norarsquos budget goal
8c + 10 le
D Suppose Nora finds party favors that cost $4 each Use a value of 4 for c and check to see if this inequality is true
8 middot 4 + 10 le 50
le 50
Module 2 73 Lesson 4
24 Creating and Solving Inequalities
Essential Question How do you write and solve an inequality that represents a real-world situation
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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pany
Is the inequality true
Could Nora buy $6 party favors for all of her guests without going over budget
Reflect
1 Why does an inequality represent Norarsquos budget calculation better than an equation
2 The solution set of an inequality consists of all values that make the statement true Describe the whole dollar amounts that are in the solution set for this situation
Explain 1 Creating and Solving Inequalities Involving the Distributive Property
You may need to use the Distributive Property before you can solve an inequality
Distributive Property If a b and c are real numbers then a(b + c) = ab + ac
The inequality sign must be reversed when multiplying or dividing both sides of an inequality by a negative number
Example 1
A Trina is buying 12 shirts for the drama club She will choose a style for the blank shirts and then pay an additional charge of $275 for each shirt to have the club logo If Trina cannot spend more than $99 how much can she spend on each blank shirt Write and solve an inequality to find the possible cost of each blank shirt
Let s represent the cost of each blank shirt
Write an inequality to represent the situation 12(s + 275) le 99
Use the Distributive Property 12s + 33 le 99
Subtraction Property of Inequality 12s + 33 - 33 le 99 - 33
Simplify 12s le 66
Division Property of Inequality 12s ___ 12 le 66 __ 12
Simplify s le 55
Module 2 74 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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oug
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Mif
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Har
cour
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lishi
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Com
pan
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Check your answer
Since s le 55 check a smaller number 12(5 + 275) le 99
Trina can order blank shirts that cost $550 or less 93 le 99 true
B Sergio needs to buy gifts for 8 friends He wants to give the same gift to all his friends and he plans to have the gifts wrapped for an additional charge of $150 each If Sergio spends at least $70 he will receive free shipping on his order Write and solve an inequality to determine how much Sergio needs to spend on each gift in order to receive free shipping
Let g be the cost of one gift
Write an inequality to represent the situation ( g + ) ge 70
Use the Distributive Property g + ge 70
Subtraction Property of Inequality g + 12 - ge 70 -
Simplify 8g ge
Division Property of Inequality 8g _
ge 58 _
Simplify g ge
Check your answer
Since g ge 725 check a larger number 8(8 + 150) ge 70
Sergio must spend at least on each gift ge 70
Reflect
3 Discussion Why is the first step in solving the inequality to use the Distributive Property instead of working inside the parentheses
Your Turn
4 Zachary is planning to send a video game to each of his two brothers If he buys the same game for both brothers and pays $475 to ship each game how much can he spend on each game without spending more than $100 Write and solve an inequality for this situation
Solve each inequality
5 4 _ 3 (6x + 9) lt 4 6 -2 ( 1 _ 4 x + 2 ) ge 5
Module 2 75 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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pany
Explain 2 Creating and Solving Inequalities with Variables on Both Sides
Some inequalities have variable terms on both sides of the inequality symbol You can solve these inequalities the same way you solved equations with variables on both sides Use the properties of inequality to collect all the variable terms on one side and all the constant terms on the other side
Example 2
A The Daily Info charges a fee of $650 plus $80 per week to run an ad The Peoplersquos Paper charges $145 per week For how many weeks must an ad run for the total cost at the Daily Info to be less expensive than the cost at the Peoplersquos Paper Let w be the number of weeks the ad runs in the paper
Write an inequality to represent the situation 650 + 80w lt 145w
Subtraction Property of Inequality 650 + 80w - 80w lt 145w - 80w
Simplify 650 lt 65w
Division Property of Inequality 650 _ 65 lt 65w _ 65
Simplify 10 lt w
The total cost at the Daily Info is less than the cost at the Peoplersquos Paper if the ad runs for more than 10 weeks
B The Home Cleaning Company charges $312 to power-wash the siding of a house plus $12 for each window Power Clean charges $36 per window and the price includes power-washing the siding How many windows must a house have to make the total cost from The Home Cleaning Company less expensive than Power Clean Let w be the number of windows
Write an inequality to represent the situation +12w lt 36w
Subtraction Property of Inequality 312 + 12w - lt 36w -
Simplify 312 lt
Division Property of Inequality 312 _ lt 24w _
Simplify lt w
A house must have more than 13 windows for The Home Cleaning Company to be less expensive than Power Clean
Reflect
7 How would the final inequality change if you divided by ndash24 in the next to last step
Your Turn
8 The school band will sell pizzas to raise money for new uniforms The supplier charges $100 plus $4 per pizza The band members sell the pizzas for $7 each Write and solve an inequality to find how many pizzas the band members will have to sell to make a profit
Module 2 76 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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oug
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Mif
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Har
cour
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Elaborate
9 Which inequality symbol would you use to represent the following words or phrases Can you come up with more examples
a at most b farther than c younger than d up to
10 Discussion How are the steps to solving an inequality similar to those for solving an equation How are they different
11 Essential Question Check-In How can you write an inequality that represents a real-world situation
Write an inequality that represents the description and then solve
1 Max has more than 5 carrots (number of carrots Max has = c)
2 Brigitte is shorter than 5 feet (Brigittersquos height = h)
3 Twice a number (x) is less than 10 4 Six more than five times a number (x) is at least twenty-one
5 Dave has $15 to spend on an $8 book and two birthday cards (c) for his friends How much can he spend on each card if he buys the same card for each friend
6 Toni can carry up to 18 lb in her backpack Her lunch weighs 1 lb her gym clothes weigh 2 lb and her books (b) weigh 3 lb each How many books can she carry in her backpack
Evaluate Homework and Practice
bull Online Homeworkbull Hints and Helpbull Extra Practice
Module 2 77 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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oug
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arcourt Publishin
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pany
Solve each inequality
7 3 (x - 2) gt -3 8 5 + 5 (x + 4) le 20 9 3 + 1 _ 2 (3 - x) lt -7
10 3 (x + 6) - 2 (x + 2) ge 10 11 5 (3 - x) -4 (2 - 3x) gt 2 12 1 _ 2 (4x - 2) - 2 _ 3 (6x + 9) le 4
13 x + 1 gt -5 (7 - 2x) 14 5 _ 3 (6x + 3) le 2x - 7
15 2x le - 2 __ 3 (4x + 4) 16 1 __ 2 (-2x - 10) gt 3 (4 - 6x)
17 -5 - 3x ge 2 (10 + 2x) + 3 18 -3 (9x + 20) ge 15x - 20
19 8 ( 1 _ 4 x - 3) + 24 lt 4 ( x + 5 ) 20 6x - 2 (x + 2) gt 2 - 3 (x + 3)
Module 2 78 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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pan
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21 Physics A crane cable can support a maximum load of 15000 kg If a bucket has a mass of 2000 kg and gravel has a mass of 1500 kg for every cubic meter how many cubic meters of gravel (g) can be safely lifted by the crane
22 Find the solution set of each inequality below and then determine which inequalities have the same solution set as 1 _ 3 ( -5x - 3 ) lt 14
a 1 _ 3 (5x + 3) gt -14 b 2 _ 5 (10x + 20) gt 44
c - 2 _ 5 (10x + 20) lt -44 d - 1 _ 3 (5x + 3) lt 14
e 2 _ 5 (10x - 20) gt -44 f 1 _ 3 (5x + 3) lt -14
HOT Focus on Higher Order Thinking
23 Explain the Error Sven is trying to find the maximum amount of time he can spend practicing the five scales of piano music he is supposed to be working on He has 60 minutes to practice piano and would like to spend at least 35 minutes playing songs instead of practicing scales So Sven sets up the following inequality where t is the number of minutes he spends on each scale and solves it
60 - 5t le 35-5t le -25
t ge 5
Sven has concluded that he should spend 5 minutes or more on each scale Is this correct If not what mistake did he make Then solve for the correct answer
Module 2 79 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
24 Critical Thinking Anika wants to determine the maximum number of tulip bulbs (t) she can purchase if each bulb costs $150 She will also need to purchase separate pots for each bulb at $125 each and a bag of potting soil for $1000 Set up an inequality to determine how many tulip bulbs Anika can purchase without spending more than $2000 and solve it Can Anika buy exactly enough bulbs and pots to spend the full $2000 Explain Can you think of a better inequality to describe the answer
25 Geometry The area of the triangle shown is no more than 10 square inches
a Write an inequality that can be used to find x
b Solve the inequality from part a c What is the maximum height of the triangle
Lesson Performance TaskWhen planning an airplane route the trip planner must be careful to consider the range the aircraft can travel and the availability of airports to stop and refuel
A large commercial jet airplane burns approximately 5 gallons of fuel per mile flown plus about 8500 gallons of fuel per trip to reach cruising altitude With a useable fuel capacity of 50000 gallons (there is additional fuel reserved for emergencies) describe the acceptable distance for which an airline could establish a non-stop flight
For flights originating from Chicago determine which cities could be safely reached by a non-stop flight
City Distance from Chicago (miles)
Bangalore India 8530
Jakarta Indonesia 9810
Johannesburg South Africa 8680
Moscow Russia 4970
Paris France 4130
Perth Australia 10970
Tokyo Japan 6300
copy H
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its copySarych
eva O
lesiaShutterstock
(2x - 3) in
4 in
Module 2 80 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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Mif
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Har
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Com
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Name Class Date
Resource Locker
Explore Truth Tables and Compound StatementsA compound statement is formed by combining two or more simple statements A compound statement can be true or false A compound statement involving AND is true when both simple statements are true A compound statement involving OR is true when either one simple statement or both are true
A Complete the truth table
P QP
True or FalseQ
True or FalseP AND Q
True or False
A dog is a mammal Red is a color
A dog is a mammal Red is not a color
A dog is a fish Red is a color
A dog is a fish Red is not a color
B P AND Q is true when
C Complete the truth table
P QP
True or FalseQ
True or FalseP OR Q
True or False
1 is an odd number 2 is an even number
1 is an odd number 2 is an odd number
1 is an even number 2 is an even number
1 is an even number 2 is an odd number
D P OR Q is true when
Reflect
1 Give two simple statements P and Q for which P AND Q is false and P OR Q is true
Module 2 81 Lesson 5
25 Creating and Solving Compound Inequalities
Essential Question How can you solve a compound inequality and graph the solution set
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Explain 1 Solving Compound Inequalities Involving ANDCombining two or more simple inequalities forms a compound inequality The graph of a compound inequality involving AND is the intersection or the overlapping region of the simple inequality graphs
Compound Inequalities AND
Words Algebra Graph
All real numbers greater than 2AND less than 6
x gt 2 AND x lt 62 lt x lt 6
All real numbers greater than or equal to 2 AND less than or equal to 6
x ge 2 AND x le 62 le x le 6
Example 1 Solve each compound inequality and graph the solutions
A 4 le x + 2 le 8
4 le x + 2 AND x + 2 le 8 Write the compound inequality using AND
4 - 2 le x + 2 - 2 x + 2 - 2 le 8 - 2 Subtract 2 from both sides of each simple inequality
2 le x x le 6 Simplify
Graph 2 le x
Graph x le 6
Graph the intersection by finding where the two graphs overlap
B -5 le 2x + 3 lt 9
-5 - le 2x + 3 - lt 9 - Subtract from each part of the inequality
le 2x lt Simplify
-8 _ le 2x _ lt 6 _ Divide each part of the inequality by
le x lt Simplify
Graph -4 le x
Graph x lt 3
Graph the intersection by finding where the two graphs overlap -1 0 1 2 3 4 5-5-4 -3 -2
0 2 4 6 8 10 12-8-6-4 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 82 Lesson 5
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Reflect
2 Discussion Explain why 2 le x le 6 can be considered the short method for writing the AND compound inequality x ge 2 AND x le 6
YourTurn
Solve each compound inequality and graph the solutions
3 -2 lt x - 3 lt 5
4 -10 lt 3x + 2 le 8
Explain 2 Solving Compound Inequalities Involving ORThe graph of a compound inequality involving OR is the union or the combined region of the simple inequality graphs
Compound Inequalities OR
Words Algebra Graph
All real numbers less than 2OR greater than 6
x lt 2 OR x gt 6
All real numbers less than or equal to 2OR greater than or equal to 6
x le 2 OR x ge 6
-1 0 1 2 3 4 5-5-4 -3 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 83 Lesson 5
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Example 2 Solve each compound inequality and graph the solutions
A -4 + x gt 1 OR -4 + x lt -3
-4 + x gt 1 OR -4 + x lt -3 Write the compound inequality using OR
-4 + 4 + x gt 1 + 4 -4 + 4 + x lt -3 + 4 Add 4 to both sides of each simple inequality
x gt 5 x lt 1 Simplify
Graph x gt 5
Graph x lt 1
Graph the union by combining the graphs
B 2x le 6 OR 3x gt 12
2x le 6 OR 3x gt 12 Write the compound inequality using OR
2x _ le 6 _ OR 3x _ gt 12 _ Divide the first simple inequality by
x le OR x gt
Graph x le 3
Graph x gt 4
Graph the union by combining the graphs
Reflect
5 Critical Thinking What kind of compound inequality has no solution
Divide the second simple inequality by
Simplify
0 1 2 3 4 5 6-4 -3 -2 -1
-0 1 2 3 4 5 6-4 -3 -2 -1
Module 2 84 Lesson 5
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Your Turn
Solve each compound inequality and graph the solutions
6 x - 5 ge -2 OR x -5 le -6
7 4x -1 lt 15 OR 8x ge 48
Explain 3 Creating Compound Inequalities From GraphsGiven a number line graph with a solution set graphed you can create a compound inequality to fit the graph
Example 3 Write the compound inequality shown by each graph
A
The shaded portion of the graph is not between two values so the compound inequality involves OR
On the left the graph shows an arrow pointing left from -1 and a solid circle so use le
The inequality is x le -1
On the right the graph shows an arrow pointing right from 7 and a solid circle so use ge
The inequality is x ge 7
The compound inequality is x le -1 OR x ge 7
B
The graph is shaded between the values and so the compound inequality involves AND
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The compound inequality is
-1 0 1 2 3 4 5-5-4 -3 -2
4 5 6 7 8 9 100 1 2 3
2 3 4 5 6 7 8-2 -1 0 1
10 2 3 4 5 6 7 8 9-1
Module 2 85 Lesson 5
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Reflect
8 What is a short method to write the compound inequality x ge 0 AND x lt 6
Your Turn
Write the compound inequality shown by each graph
9
10
Explain 4 Expressing Acceptable Levels with Compound Inequalities
You can express quality-controls levels in real-world problems using compound inequalities
Example 4 Write a compound inequality to represent the indicated quality-control level and graph the solutions
A The recommended pH level for swimming pool water is between 72 and 76 inclusive
Let p be the pH level of swimming pool water
72 is less than or equal to pH level is less than or equal to 76
72 le p le 76
The compound inequality is 72 le p le 76
Graph the solutions
0-10 -8-9 -7-6 -5-4 -3 -2 -1
71 72 73 74 75 76 77 78 79 8070
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 86 Lesson 5
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B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
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bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
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oug
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pan
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Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
arcourt Publishin
g Com
pany bull Im
age C
redits copy
Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
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oug
hton
Mif
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Com
pan
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mag
e C
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copy
bik
erid
erlo
nd
onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
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oug
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arcourt Publishin
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The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
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oug
hton
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cour
t Pub
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Com
pan
y
The term 695(p + 8) represents 695 represents the cost of (p + 8) represents that Jill bought
Interpret the expression 8p + 695(p + 8)
The expression represents that Jill bought
Your Turn
Interpret the algebraic expression corresponding to the given context
3 George is buying watermelons and pineapples to make fruit salad He buys w watermelons at $449 each and p pineapples at $5 each What does the expression 449w + 5p represent
4 Sandi buys 5 fewer packages of pencils than p packages of pens Pencils costs $225 per package and pens costs $3 per package What does the expression 3p + 225(p - 5) represent
Explain 2 Comparing Algebraic ExpressionsGiven two algebraic expressions involving two variables we can compare whether one is greater or less than the other We can denote the inequality between the expressions by using lt or gt symbols If the expressions are the same or equivalent expressions we denote this equality by using =
Suppose x and y give the populations of two different cities where x gt y Compare the expressions and tell which of the given pair is greater
Example 1
x + y and 2x
The expression 2x is greater
bull Putting the lesser population y together with the greater population x gives a population that is less than double the greater population
x _ y and y _ x
Since x gt y x _ y will be than 1 and y _ x will be than 1
So x _ y y _ x
Your Turn
Suppose x and y give the populations of two different cities where x gt y and y gt 0 Compare the expressions and tell which of the given pair is greater
5 x _ x + y and x + y
_ x 6 2(x + y) and (x + y)2
Module 2 47 Lesson 1
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oug
hton Mifflin H
arcourt Publishin
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Explain 3 Modeling Expressions in ContextThe table shows some words and phrases associated with the four basic arithmetic operations These words and phrases can help you translate a real-world situation into an algebraic expression
Operation Words Examples
Addition the sum of added to plus more than increased by total altogether and
1 A number increased by 22 The sum of n and 23 n + 2
Subtraction less than minus subtracted from the difference of take away taken from reduced by
1 The difference of a number and 22 2 less than a number3 n - 2
Multiplication times multiplied by the product of percent of
1 The product of 06 and a number2 60 of a number3 06n
Division divided by division of quotient of divided into ratio of
1 The quotient of a number and 52 A number divided by 53 n divide 5 or n __ 5
Example 3 Write an algebraic expression to model the given context Give your answer in simplest form
the price of an item plus 6 sales tax
Price of an item + 6 sales tax
p + 006p
The algebraic expression is p + 006p or 106p
the price of a car plus 85 sales tax
The price of a car +
+
The algebraic expression is
or
Reflect
7 Use the Distributive Property to show why p + 006p = 106p
8 What could the expression 3(p + 006p) represent Explain
Your Turn
Write an algebraic expression to model the given context Give your answer in simplest form
9 the number of gallons of water in a tank that already has 300 gallons in it after being filled at 35 gallons per minute for m minutes
10 the original price p of an item less a discount of 15
Module 2 48 Lesson 1
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Elaborate
11 When given an algebraic expression involving subtraction why is it best to rewrite the expression using addition before identifying the terms
12 How do you interpret algebraic expressions in terms of their context
13 How do you simplify algebraic expressions
14 Essential Question Check In How do you write algebraic expressions to model quantities
bull Online Homeworkbull Hints and Helpbull Extra Practice
Evaluate Homework and PracticeIdentify the terms and the coefficients of the expression
1 -20 + 5p - 7z 2 8x - 20y - 10
Identify the factors of the terms of the expression
3 5 + 6a + 11b 4 13m - 2n
5 Erin is buying produce at a store She buys c cucumbers at $099 each and a apples at $079 each What does the expression 099c + 079a represent
6 The number of bees that visit a plant is 500 times the number of years the plant is alive where t represents the number of years the plant is alive What does the expression 500t represent
Evaluate Homework and Practice
Module 2 49 Lesson 1
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oug
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arcourt Publishin
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Leonard
LenzC
orbis
7 Lorenzo buys 3 shirts at s dollars apiece and 2 pairs of pants at p dollars a pair What does the expression 3s + 2p represent
8 If a car travels at a speed of 25 mih for t hours then travels 45 mih for m hours what does the expression 25t + 45m represent
9 The price of a sandwich is $150 more than the price of a smoothie which is d dollars What does the expression d + 15 represent
10 A bicyclist travels 1 mile in 5 minutes If m represents minutes what does the expression m __ 5 represent
11 What are the factors of the expression (y - 2)(x + 3)
12 Explain the Error A student wrote that there are two terms in the expression 3p - (7 - 4q) Explain the studentrsquos error
13 Yolanda is buying supplies for school She buys n packages of pencils at $140 per package and m pads of paper at $120 each What does each term in the expression 14n + 12m represent What does the entire expression represent
14 Chris buys p pairs of pants and 4 more shirts than pairs of pants Shirts cost $18 each and pair of pants cost $25 each What does each term in the expression 25p + 18(p + 4) represent What does the entire expression represent
Module 2 50 Lesson 1
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oug
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ssie
W
alke
rLi
ved
In Im
ages
Cor
bis
Suppose a and b give the populations of two states where a gt b Compare the expressions and tell which of the given pair is greater or if the expressions are equal
15 b _ a + b
and 05
16 a + 13c and b + 13c where c is the population of a third state
17 a - b _ 2 and a - b _ 2
18 a + b and 2b
19 5(a + b) and (a + b)5
Write an algebraic expression to model the given context Give your answer in simplest form
20 the price s of a pair of shoes plus 5 sales tax 21 the original price p of an item less a discount of 20
22 the price h of a recently bought house plus 10 property tax
23 the principal amount P originally deposited in a bank account plus 03 interest
Module 2 51 Lesson 1
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oug
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pany
24 Match each statement with the algebraic expression that models it
A the price of a winter coat and a 20 discount x + 002x = 102x
B the base salary of an employee and a 2 salary increase x - 020x = 080x
C the cost of groceries and a 2 discount with coupons x + 020x = 120x
D the number of students attending school last year and a 20 increase from last year x - 002x = 098x
HOT Focus on Higher Order Thinking
25 Critique Reasoning A student is given the rectangle and the square shown The student states that the two figures have the same perimeter Is the student correct Explain your reasoning
26 Multi-Step Yon buys tickets to a concert for himself and a friend There is a tax of 6 on the price of the tickets and an additional booking fee of $20 for the transaction Write an algebraic expression to represent the price per person Simplify the expression if possible
x + 2
x + 2x
x + 4
Module 2 52 Lesson 1
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27 Persevere in Problem Solving Jerry is planting white daisies and red tulips in his garden and he wants to choose a pattern in which the tulips surround the daisies He uses tiles to generate patterns starting with two rows of three daisies He surrounds these daisies with a border of tulips The design continues as shown
a Jerry writes the expression 8(b - 1) + 10 for the number of tulips in each border wherein b is the border number and b ge 1 Explain why Jerryrsquos expression is correct
b Elaine wants to start with two rows of four daisies Her reasoning is that Jerry started with two rows of three daisies and his expression was 8(b - 1) + 10 so if she starts with two rows of four daisies her expression will be 10(b - 1) + 10 Is Elainersquos statement correct Explain
Border 1 Border 2 Border 3
Module 2 53 Lesson 1
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
Lesson Performance Task
Becky and Michele are both shopping for a new car at two different dealerships Dealership A is offering $500 cash back on any purchase while Dealership B is offering $1000 cash back The tax rate is 5 at Dealership A but 8 at Dealership B Becky wants to buy a car that is $15000 and Michele is planning to buy a car that costs $20000 Use algebraic expressions to help you answer the following questions
a At which dealership will Becky get the better deal How much does she save
b At which dealership will Michele get the better deal How much does she save
c What generalization can you make that would help any shopper know which dealership has the better deal [Hint At what price point would the two deals be equal]
copy H
oug
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age C
redits copy
Tom G
rillC
orbis
Module 2 54 Lesson 1
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pan
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Name Class Date
Resource Locker
Explore Creating Equations from Verbal Descriptions
You can use what you know about writing algebraic expressions to write an equation that represents a real-world situation
Suppose Cory and his friend Walter go to a movie Each of their tickets costs the same amount and they share a frozen yogurt that costs $550 The total amount they spend is $1990 How can you write an equation that describes the situation
A Identify the important information
The word tells you that the relationship describes an equation
The word total tells you that the operation involved in the relationship is
What numerical information do you have
What is the unknown quantity
B Write a verbal description
Choose a name for the variable In this case use c for
The verbal description is Twice the cost of plus the cost
of equals
C To write an equation write a numerical or expression for each quantity
and insert an equal sign in the appropriate place An equation is
Reflect
1 How can you use a verbal model to write an equation for the situation described
Module 2 55 Lesson 2
22 Creating and Solving EquationsEssential Question How do you use an equation to model and solve a real-world problem
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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arcourt Publishin
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pany bull Im
age C
redits D
igital
Vision
Getty Im
ages
2 Could you write a different equation to describe the situation Explain your reasoning
Explain 1 Creating and Solving Equations Involving the Distributive Property
When you create an equation to model a real-world problem your equation may involve the Distributive Property When you solve a real-world problem you should always check that your answer makes sense
Example 1 Write and solve an equation to solve each problem
A Aaron and Alice are bowling Alicersquos score is twice the difference of Aaronrsquos score and 5 The sum of their scores is 320 Find each studentrsquos bowling score
Write a verbal description of the basic situation
The sum of Aaronrsquos score and Alicersquos score is 320
Choose a variable for the unknown quantity and write an equation to model the detailed situation
Let a represent Aaronrsquos score Then 2 (a - 5) represents Alicersquos score
a + 2 (a - 5) = 320
Solve the equation for a
a + 2 (a - 5) = 320
a + 2a - 10 = 320 Distributive Property
3a - 10 = 320
3a - 10 + 10 = 320 + 10 Addition Property of Equality
3a = 330
3a _ 3 = 330 _ 3 Division Property of Equality
a = 110
So Aaronrsquos score is 110 and Alicersquos score is 2 (a - 5) = 2 (110 - 5) = 2 (105) = 210
Check that the answer makes sense
110 + 210 = 320 so the answer makes sense
B Mari Carlos and Amanda collect stamps Carlos has five more stamps than Mari and Amanda has three times as many stamps as Carlos Altogether they have 100 stamps Find the number of stamps each person has
Write a verbal description of the basic situation
Module 2 56 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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oug
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Mif
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Har
cour
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lishi
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Com
pan
y
Choose a variable for the unknown quantity and write an equation to model the detailed situation
Let s represent the number of stamps Mari has Then Carlos has stamps
and Amanda has stamps
s + + 3 ( ) =
Solve the equation for s
s + + 3 ( ) =
s + s + 5 + 3s + = Distributive Property
+ = Combine like terms
s = Subtraction Property of Equality
s = Division Property of Equality
So Mari has stamps Carlos has stamps and Amanda
has stamps
Check that the answer makes sense
+ + = the answer makes sense
=
Reflect
3 Would a fractional answer make sense in this situation
4 Discussion What might it mean if a check revealed that the answer to a real-world problem did not make sense
Module 2 57 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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arcourt Publishin
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pany
Your Turn
Write and solve an equation to solve the problem
5 A rectangular garden is fenced on all sides with 256 feet of fencing The garden is 8 feet longer than it is wide Find the length and width of the garden
Explain 2 Creating and Solving Equations with Variables on Both Sides
In some equations variables appear on both sides You can use the properties of equality to collect the variable terms so that they all appear on one side of the equation
Example 2 Write and solve an equation to solve each problem
A Janine has job offers at two companies One company offers a starting salary of $28000 with a raise of $3000 each year The other company offers a starting salary of $36000 with a raise of $2000 each year In how many years would Janinersquos salary be the same with both companies What will the salary be
Write a verbal description of the basic situation
Let n represent the number of years it takes for the salaries to be equal
Base Salary A plus $3000 per year raise = Base Salary B + $2000 per year raise
28000 + 3000n = 36000 + 2000n
28000 + 3000n - 2000n = 36000 + 2000n - 2000n Subtraction Property of Equality
28000 + 1000n = 36000 Combine like terms
28000 + 1000n - 28000 = 36000 - 28000 Subtraction Property of Equality
1000n = 8000 1000n _ 1000 = 8000 _ 1000 Division Property of Equality
n = 8
28000 + 3000 (8) = 36000 + 2000 (8)
52000 = 52000
In 8 years the salaries offered by both companies will be $52000
(w + 8) feet
w feet
Module 2 58 Lesson 2
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B One moving company charges $800 plus $16 per hour Another moving company charges $720 plus $21 per hour At what number of hours will the charge by both companies be the same What is the charge
Write a verbal description of the basic situation Let t represent the number of hours that the move takes
Moving Charge A plus $16 per hour = Moving Charge B plus $21 per hour
800 + t = 720 + t
800 + t - t = 720 + t - t Subtraction Property of Equality
800 = 720 + t
800 - 720 = 720 + t - 720 Subtraction Property of Equality
= t
_ = t _
Division Property of Equality
t =
The charges are the same for a job that takes hours
Substitute the value 16 in the original equation
800 + 16t = 720 + 21t
800 + 16 ( ) = 720 + 21 ( ) 800 + = 720 +
=
After hours the moving charge for both companies will be
Reflect
6 Suppose you collected the variable terms on the other side of the equal sign to solve the equation Would that affect the solution
Module 2 59 Lesson 2
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Your Turn
Write and solve an equation to solve each problem7 Claire bought just enough fencing to enclose either a
rectangular garden or a triangular garden as shown The two gardens have the same perimeter How many feet of fencing did she buy
8 A veterinarian is changing the diets of two animals Simba and Cuddles Simba currently consumes 1200 Calories per day That number will increase by 100 Calories each day Cuddles currently consumes 3230 Calories a day That number will decrease by 190 Calories each day The patterns will continue until both animals are consuming the same number of Calories each day In how many days will that be How many Calories will each animal be consuming each day then
Explain 3 Constructing Equations from an Organized TableYou can use a table to organize information and see relationships
Example 3 Construct and solve an equation to solve the problem
Kim works 4 hours more each day than Jill does and Jack works 2 hours less each day than Jill does Over 2 days the number of hours Kim works is equal to the difference of 4 times the number of hours Jack works and the number of hours Jill works How many hours does each person work each day
Analyze Information
Identify the important information
bull Kim works hours more per day than Jill does
bull Jack works hours less per day than Jill does
Formulate a Plan
Make a table using the information given Let x be the number of hours Jill works in one day
Hours Worked Per Day Hours Worked Over 2 Days
Kim
Jill
Jack
Over 2 days the number of hours Kim works is equal to the difference of 4 times the number of hours Jack works and the number of hours Jill works
(3x - 3)(x - 3)
(2x - 1) (2x - 1)
2x
Module 2 60 Lesson 2
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Solve
2 (x + 4) = 4 2 (x - 2) - 2x
2 (x + 4) = (x - 2) - 2x Simplify
2x + = 8x - - 2x Distributive Property
2x + 8 = x - 16
2x + 8 + = 6x - 16 + Addition Property of Equality
2x + = 6x
2x + 24 - x = 6x - x Subtraction Property of Equality
24 = x
24 _ = x _ Division Property of Equality
= x
Jill works hours per day Kim works hours per day and Jack works
hours per day
Justify and Evaluate
Substitute x = 6 into the original equation
2 (6 + 4) = 4 2 (6 - 2) - 2x
2 ( ) = 8 ( ) - 2 ( ) =
Your Turn
Write and solve an equation to solve the problem
9 Lisa is 10 centimeters taller than her friend Ian Ian is 14 centimeters taller than Jim Every month their heights increase by 2 centimeters In 7 months the sum of Ianrsquos and Jimrsquos heights will be 170 centimeters more than Lisarsquos height How tall is Ian now
Height now Height after 7 months
Module 2 61 Lesson 2
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Elaborate
10 How can you use properties to solve equations with variables on both sides
11 How is a table helpful when constructing equations
12 When solving a real-world problem to find a personrsquos age would a negative solution make sense Explain
13 Essential Question Check-In How do you write an equation to represent a real-world situation
bull Online Homeworkbull Hints and Helpbull Extra Practice
Write an equation for each description
1 The sum of 14 and a number is equal to 17 2 A number increased by 10 is 114
3 The difference between a number and 12 is 20 4 Ten times the sum of half a number and 6 is 8
5 Two-thirds a number plus 4 is 7 6 Tanmayi wants to raise $175 for a school fundraiser She has raised $120 so far How much more does she need to reach her goal
7 Hector is visiting a cousin who lives 350 miles away He has driven 90 miles How many more miles does he need to drive to reach his cousinrsquos home
8 The length of a rectangle is twice its width The perimeter of the rectangle is 126 feet
Evaluate Homework and Practice
Module 2 62 Lesson 2
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Pete
r K
imS
hutt
erst
ock
Write and solve an equation for each situation
9 In one baseball season Peter hit twice the difference of the number of home runs Alice hit and 6 Altogether they hit 18 home runs How many home runs did each player hit that season
10 The perimeter of a parallelogram is 72 meters The width of the parallelogram is 4 meters less than its length Find the length and the width of the parallelogram
11 One month Ruby worked 6 hours more than Isaac and Svetlana worked 4 times as many hours as Ruby Together they worked 126 hours Find the number of hours each person worked
12 In one day Annie traveled 5 times the sum of the number of hours Brian traveled and 2 Together they traveled 20 hours Find the number of hours each person traveled
13 Xian and his cousin Kai both collect stamps Xian has 56 stamps and Kai has 80 stamps The boys recently joined different stamp-collecting clubs Xianrsquos club will send him 12 new stamps per month Kairsquos club will send him 8 new stamps per month After how many months will Xian and Kai have the same number of stamps How many stamps will each have
14 Kenya plans to make a down payment plus monthly payments in order to buy a motorcycle At one dealer she would pay $2500 down and $150 each month At another dealer she would pay $3000 down and $125 each month After how many months would the total amount paid be the same for both dealers What would that amount be
ℓ meters
(ℓ - 4) meters
Module 2 63 Lesson 2
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15 Community Gym charges a $50 membership fee and a $55 monthly fee Workout Gym charges a $200 membership fee and a $45 monthly fee After how many months will the total amount of money paid to both gyms be the same What will the amount be
16 Tina is saving to buy a notebook computer She has two options The first option is to put $200 away initially and save $10 every month The second option is to put $100 away initially and save $30 every month After how many months would Tina save the same amount using either option How much would she save with either option
Use the table to answer each question
Starting Salary Yearly Salary Increase
Company A $24000 $3000
Company B $30000 $2400
Company C $36000 $2000
17 After how many years are the salaries offered by Company A and Company B the same
18 After how many years are the salaries offered by Company B and Company C the same
19 Paul started work at Company B ten years ago at the salary shown in the table At the same time Sharla started at Company C at the salary shown in the table Who earned more during the last year How much more
20 Georgersquos page contains twice as many typed words as Billrsquos page and Billrsquos page contains 50 fewer words than Charliersquos page If each person can type 60 words per minute after one minute the difference between twice the number of words on Billrsquos page and the number of words on Charliersquos page is 210 How many words did Billrsquos page contain initially Use a table to organize the information
Initial number of words
Total number of words after one minute
Module 2 64 Lesson 2
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cour
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pan
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21 Geometry Sammie bought just enough fencing to border either a rectangular plot or a square plot as shown The perimeters of the plots are the same How many meters of fencing did she buy
HOT Focus on Higher Order Thinking
22 Justify Reasoning Suppose you want to solve the equation 2a + b = 2a where a and b are nonzero real numbers Describe the solution to this equation Justify your description
23 Multi-step A patio in the shape of a rectangle is fenced on all sides with 134 feet of fencing The patio is 5 feet less wide than it is long
a What information can be used to solve the problem How can you find the information
b Describe how to find the area of the patio What is the area of the patio
24 Explain the Error Kevin and Brittany write an equation to represent the following relationship and both students solve their equation Who found the correct equation and solution Why is the other person incorrect
5 times the difference of a number and 20 is the same as half the sum of 4 more than 4 times a number
Kevin Brittany
5 (x - 20) = 1 _ 2 (4x + 4) 5 (20 + x) = 1 _ 2 (4x + 4)
5x - 100 = 2x + 2 100 - 5x = 2x + 2
3x - 100 = 2 100 - 7x = 2
3x = 102 -7x = -98
x = 34 x = 14
(3x + 2) meters
(x + 2) meters
(x + 2) meters
(x - 1) meters
ℓ feet
(ℓ - 5) feet
Module 2 65 Lesson 2
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oug
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25 What If Alexa and Zack are solving the following problem
The number of miles on Car A is 50 miles more than the number of miles on Car B and the number of miles on Car B is 30 miles more than the number of miles on Car C All the cars travel 50 miles in 1 hour After 1 hour twice the number of miles on Car A is 70 miles less than 3 times the number of miles on Car C How many miles were there on Car B initially
Alexa assumes there are m miles on Car B Zack assumes there are m miles on Car C Will Zackrsquos answer be the same as Alexarsquos answer Explain
Lesson Performance Task
Stacy Oliver and Jivesh each plan to put a certain amount of money into their savings accounts that earn simple interest of 6 per year Stacy puts $550 more than Jivesh and Oliver puts in 2 times as much as Jivesh After a year the amount in Stacyrsquos account is 2 times the sum of $212 and the amount in Oliverrsquos account How much does each person initially put into his or her account Who had the most money in his or her account after a year Who had the least Explain
Zackrsquos Table Initial Miles
Miles after One Hour
Alexarsquos Table Initial Miles
Miles after One Hour
Amount in Account Initially Amount in Account after One Year
Module 2 66 Lesson 2
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oug
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Name Class Date
Resource Locker
Explore Rearranging Mathematical FormulasLiteral Equations are equations that contain two or more variables There are many literal equations in the form of math science and engineering formulas These formulas may seem like they can only be solved for the variable that is isolated on one side of the formula By using inverse operations and the properties of equality a formula can be rearranged so any variable in the formula can be isolated It is no different than how equations are solved by using inverse operations and the properties of equality
How can you solve the equation 42 = 6x
A42 _ = 6x _ What is the reason for dividing
Why divide by
= x By rearranging the equation x was isolated and the solution was found
The mathematical formula for the volume of a rectangular prism B = Vh or V = ℓwh is a literal equation V represents volume ℓ represents length w represents width and h represents height Using inverse operations the formula can be rearranged to solve for any one of the variables that might be unknown Like solving for x a formula can be rearranged to isolate a variable
B In the formula V = ℓwh the variable h needs to be isolated
The operation of is used in the formula The inverse
operation should be used
to isolate
C V _____ = ℓwh _____
V _ =
The formula rearranged in this way can easily produce the height of the rectangular prism when the volume length and width are known
Reflect
1 Using the formula for a rectangular prism rewrite the formula to solve for ℓ
ℓw
h
Module 2 67 Lesson 3
23 Solving for a VariableEssential Question How do you rewrite formulas and literal equations
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Photo
grap
hyAurora Ph
otosCorb
is
Explain 1 Rearranging Scientific FormulasUse inverse operations to isolate the unknown variable in a scientific formula
The formula for density is D = m __ V Lead has a very high density of 11340 kg m 3 Plastic foam has a very low density of 75 kg m 3 The formula for density can be rearranged to solve for V volume or m mass
Example 1
A A sinker on a fishing line is made of lead and has a volume of 0000015 m 3 What is the mass of the sinker
The density formula can be rearranged to isolate m the mass The values for volume and density can then be substituted into the formula to find the mass
D = m _ V
DV = ( m _ V ) V DV = m
(11340 kg m 3 ) (0000015 m 3 ) = m
017 kg asymp m
B The design for a life preserver requires 03 kilogram of plastic foam to provide proper buoyancy What is the volume of the plastic foam required
Rearrange the density formula to isolate V
D = m _ V
(D) V = m _ V
DV =
DV _ = m _
V =
Now substitute the given values
V = _
V = m 3
Your Turn
2 For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Determine the altitude in feet when t is -275 ∘F and g is 60 ∘F
Module 2 68 Lesson 3
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Explain 2 Rearranging Literal EquationsUsing inverse operations to rearrange literal equations can be applied to any formula The interest formula I = prt is another example of a literal equation In the formula I represents interest p the principal or the initial amount to which interest will be applied r the rate at which interest will be paid and t is the time in years
Example 2
A Find the number of years used in the calculation of a $1000 loan at an interest rate of 5 with interest totaling $600
Solve the formula for t
I = prt
I _ pr = prt
_ pr
I _ pr = t
Substitute the given values Since the interest rate is 5 r = 005$600 __
$1000 middot 005 = t
12 = t
So the length of time for the loan is 12 years
B Determine the interest rate for a $2000 loan that will be paid off in 4 years with interest totaling $640 In order to find the interest rate solve the formula for r
I = prt
I _ = prt _
_ = r
Now substitute the values and simplify
__
( ) ( ) = r
008 = r
So the interest rate is per year
Your Turn
3 The formula y = mx + b is the slope-intercept form of the equation of a line Solve the equation for m
Module 2 69 Lesson 3
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oug
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bull Online Homeworkbull Hints and Helpbull Extra Practice
Solve for the indicated variable in each mathematical formula
1 C = 2πr for r 2 A = 1 __ 2 bh for b 3 y = mx + b for x
4 A = 1 __ 2 (a + b)h for h 5 V = πr2h for h 6 SA = 2πr2 + 2πrh for h
Solve for the indicated variable in each scientific formula
7 d = rt for t 8 PV = nRT for T
9 A = FV - OV _______ T for OV 10 C = Wtc _ 1000 for W
Evaluate Homework and Practice
Elaborate
4 Discussion What could be a reason for isolating a variable in a literal equation
5 Describe a situation in which a formula could be used more easily if it were rearranged Include the formula in your description
6 Essential Question Check-In How do you isolate a variable
Module 2 70 Lesson 3
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cour
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pan
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mag
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copyO
cean
C
orb
is
Solve for the indicated variable in each literal equation
11 2p + 5r = q for p 12 -10 = xy + z for x 13 a __ b = c for b
14 h - 4 _ j = k for j 15 x __ 5 - g = a for x 16 5p + 9c = p for c
17 2 __ 5 (z + 1) = y for z 18 g (h + 2 __ 3 ) = 1 for h 19 a(n - 3) + 8 = bn for n
20 Which is a possible way to rewrite the equation y = 3x + 3b to solve for b
A b = y - 3x
_ 3 C b = y - 3
_____ 3x
B b = 3(y - 3x) D b = x(y - 3)
21 Sports To find a baseball pitcherrsquos earned run average (ERA) you can use the formula Ei = 9r in which E represents ERA i represents the number of innings pitched and r represents the number of earned runs allowed Solve the equation for E What is a pitcherrsquos ERA if he allows 5 earned runs in 18 innings pitched
22 Meteorology For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Solve the equation for a If the atmospheric temperature is -655 ∘F and the ground temperature is 57 ∘F what is the altitude
Module 2 71 Lesson 3
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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arcourt Publishin
g Com
pany bull Im
age C
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Rand
y D
uch
aineA
lamy
HOT Focus on Higher Order Thinking
23 Explain the Error A student was asked to use the formula for the perimeter of a rectangle P = 2ℓ + 2w to solve for ℓ The student came up with an answer P - 2w = 2ℓ What error did the student make Explain Then solve for ℓ
24 Multi-Step The formula c = 5p + 215 relates c the total cost in dollars of hosting a birthday party at a skating rink to p the number of people attending If Alliersquos parents are willing to spend $300 for a party how many people can attend
25 Multi-Step The formula for the area of a triangle is A = 1 __ 2 bh in which b represents the length of thebase and h represents the height If a triangle has an area of 192 mm2 and the height is 12 mm what is the measure of the base
Lesson Performance TaskThe following table shows the average low temperatures in Fahrenheit for the city of Boston for several months during the year The formula F = 9 __ 5 C + 32 allows you to determine the temperature in Fahrenheit when given the temperature in Celsius
MonthTemperature in
FahrenheitTemperature in
Celsius
January 22deg
April 41deg
July 65deg
October 47deg
December 28deg
a Use the information given to determine the average low temperatures in Celsius
b Would it ever be possible for the temperature in Celsius to have a greater value than the temperature in Fahrenheit Explain why or why not
Module 2 72 Lesson 3
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
Name Class Date
Resource Locker
copy H
oug
hton
Mif
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Har
cour
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Com
pan
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mag
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edit
s copy
Patr
ick
Lan
eSo
mos
Imag
esC
orb
is
Explore Creating Inequalities from Verbal DescriptionsAn inequality is a statement that compares two expressions that are not strictly equal by using one of the following inequality signs
Symbol Meaning
lt is less than
le is less than or equal to
gt is greater than
ge is greater than or equal to
ne is not equal to
You have probably seen a sign at an amusement park saying something like ldquoYou must be at least 48 inches tall to ride this riderdquo This statement could be written as h ge 48 in where h represents the height of a person allowed to ride
Nora is planning a birthday party for her little sister Colleen Norarsquos budget will allow her to spend no more than $50 for party supplies Eight children including Colleen will attend the party and Nora wants to determine how much she could spend on party favors for each child She will also purchase a cake for $10 Write an inequality that represents the situation and find possible solutions
A First let c represent the cost of a party favor for each child Write an expression for the total cost of the party as a function of c
c +
B Which inequality symbol should be used to represent the phrase ldquono more thanrdquo
C Write the inequality that represents Norarsquos budget goal
8c + 10 le
D Suppose Nora finds party favors that cost $4 each Use a value of 4 for c and check to see if this inequality is true
8 middot 4 + 10 le 50
le 50
Module 2 73 Lesson 4
24 Creating and Solving Inequalities
Essential Question How do you write and solve an inequality that represents a real-world situation
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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arcourt Publishin
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pany
Is the inequality true
Could Nora buy $6 party favors for all of her guests without going over budget
Reflect
1 Why does an inequality represent Norarsquos budget calculation better than an equation
2 The solution set of an inequality consists of all values that make the statement true Describe the whole dollar amounts that are in the solution set for this situation
Explain 1 Creating and Solving Inequalities Involving the Distributive Property
You may need to use the Distributive Property before you can solve an inequality
Distributive Property If a b and c are real numbers then a(b + c) = ab + ac
The inequality sign must be reversed when multiplying or dividing both sides of an inequality by a negative number
Example 1
A Trina is buying 12 shirts for the drama club She will choose a style for the blank shirts and then pay an additional charge of $275 for each shirt to have the club logo If Trina cannot spend more than $99 how much can she spend on each blank shirt Write and solve an inequality to find the possible cost of each blank shirt
Let s represent the cost of each blank shirt
Write an inequality to represent the situation 12(s + 275) le 99
Use the Distributive Property 12s + 33 le 99
Subtraction Property of Inequality 12s + 33 - 33 le 99 - 33
Simplify 12s le 66
Division Property of Inequality 12s ___ 12 le 66 __ 12
Simplify s le 55
Module 2 74 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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oug
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Mif
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Har
cour
t Pub
lishi
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Com
pan
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Check your answer
Since s le 55 check a smaller number 12(5 + 275) le 99
Trina can order blank shirts that cost $550 or less 93 le 99 true
B Sergio needs to buy gifts for 8 friends He wants to give the same gift to all his friends and he plans to have the gifts wrapped for an additional charge of $150 each If Sergio spends at least $70 he will receive free shipping on his order Write and solve an inequality to determine how much Sergio needs to spend on each gift in order to receive free shipping
Let g be the cost of one gift
Write an inequality to represent the situation ( g + ) ge 70
Use the Distributive Property g + ge 70
Subtraction Property of Inequality g + 12 - ge 70 -
Simplify 8g ge
Division Property of Inequality 8g _
ge 58 _
Simplify g ge
Check your answer
Since g ge 725 check a larger number 8(8 + 150) ge 70
Sergio must spend at least on each gift ge 70
Reflect
3 Discussion Why is the first step in solving the inequality to use the Distributive Property instead of working inside the parentheses
Your Turn
4 Zachary is planning to send a video game to each of his two brothers If he buys the same game for both brothers and pays $475 to ship each game how much can he spend on each game without spending more than $100 Write and solve an inequality for this situation
Solve each inequality
5 4 _ 3 (6x + 9) lt 4 6 -2 ( 1 _ 4 x + 2 ) ge 5
Module 2 75 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
arcourt Publishin
g Com
pany
Explain 2 Creating and Solving Inequalities with Variables on Both Sides
Some inequalities have variable terms on both sides of the inequality symbol You can solve these inequalities the same way you solved equations with variables on both sides Use the properties of inequality to collect all the variable terms on one side and all the constant terms on the other side
Example 2
A The Daily Info charges a fee of $650 plus $80 per week to run an ad The Peoplersquos Paper charges $145 per week For how many weeks must an ad run for the total cost at the Daily Info to be less expensive than the cost at the Peoplersquos Paper Let w be the number of weeks the ad runs in the paper
Write an inequality to represent the situation 650 + 80w lt 145w
Subtraction Property of Inequality 650 + 80w - 80w lt 145w - 80w
Simplify 650 lt 65w
Division Property of Inequality 650 _ 65 lt 65w _ 65
Simplify 10 lt w
The total cost at the Daily Info is less than the cost at the Peoplersquos Paper if the ad runs for more than 10 weeks
B The Home Cleaning Company charges $312 to power-wash the siding of a house plus $12 for each window Power Clean charges $36 per window and the price includes power-washing the siding How many windows must a house have to make the total cost from The Home Cleaning Company less expensive than Power Clean Let w be the number of windows
Write an inequality to represent the situation +12w lt 36w
Subtraction Property of Inequality 312 + 12w - lt 36w -
Simplify 312 lt
Division Property of Inequality 312 _ lt 24w _
Simplify lt w
A house must have more than 13 windows for The Home Cleaning Company to be less expensive than Power Clean
Reflect
7 How would the final inequality change if you divided by ndash24 in the next to last step
Your Turn
8 The school band will sell pizzas to raise money for new uniforms The supplier charges $100 plus $4 per pizza The band members sell the pizzas for $7 each Write and solve an inequality to find how many pizzas the band members will have to sell to make a profit
Module 2 76 Lesson 4
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oug
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Mif
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Har
cour
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pan
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Elaborate
9 Which inequality symbol would you use to represent the following words or phrases Can you come up with more examples
a at most b farther than c younger than d up to
10 Discussion How are the steps to solving an inequality similar to those for solving an equation How are they different
11 Essential Question Check-In How can you write an inequality that represents a real-world situation
Write an inequality that represents the description and then solve
1 Max has more than 5 carrots (number of carrots Max has = c)
2 Brigitte is shorter than 5 feet (Brigittersquos height = h)
3 Twice a number (x) is less than 10 4 Six more than five times a number (x) is at least twenty-one
5 Dave has $15 to spend on an $8 book and two birthday cards (c) for his friends How much can he spend on each card if he buys the same card for each friend
6 Toni can carry up to 18 lb in her backpack Her lunch weighs 1 lb her gym clothes weigh 2 lb and her books (b) weigh 3 lb each How many books can she carry in her backpack
Evaluate Homework and Practice
bull Online Homeworkbull Hints and Helpbull Extra Practice
Module 2 77 Lesson 4
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pany
Solve each inequality
7 3 (x - 2) gt -3 8 5 + 5 (x + 4) le 20 9 3 + 1 _ 2 (3 - x) lt -7
10 3 (x + 6) - 2 (x + 2) ge 10 11 5 (3 - x) -4 (2 - 3x) gt 2 12 1 _ 2 (4x - 2) - 2 _ 3 (6x + 9) le 4
13 x + 1 gt -5 (7 - 2x) 14 5 _ 3 (6x + 3) le 2x - 7
15 2x le - 2 __ 3 (4x + 4) 16 1 __ 2 (-2x - 10) gt 3 (4 - 6x)
17 -5 - 3x ge 2 (10 + 2x) + 3 18 -3 (9x + 20) ge 15x - 20
19 8 ( 1 _ 4 x - 3) + 24 lt 4 ( x + 5 ) 20 6x - 2 (x + 2) gt 2 - 3 (x + 3)
Module 2 78 Lesson 4
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21 Physics A crane cable can support a maximum load of 15000 kg If a bucket has a mass of 2000 kg and gravel has a mass of 1500 kg for every cubic meter how many cubic meters of gravel (g) can be safely lifted by the crane
22 Find the solution set of each inequality below and then determine which inequalities have the same solution set as 1 _ 3 ( -5x - 3 ) lt 14
a 1 _ 3 (5x + 3) gt -14 b 2 _ 5 (10x + 20) gt 44
c - 2 _ 5 (10x + 20) lt -44 d - 1 _ 3 (5x + 3) lt 14
e 2 _ 5 (10x - 20) gt -44 f 1 _ 3 (5x + 3) lt -14
HOT Focus on Higher Order Thinking
23 Explain the Error Sven is trying to find the maximum amount of time he can spend practicing the five scales of piano music he is supposed to be working on He has 60 minutes to practice piano and would like to spend at least 35 minutes playing songs instead of practicing scales So Sven sets up the following inequality where t is the number of minutes he spends on each scale and solves it
60 - 5t le 35-5t le -25
t ge 5
Sven has concluded that he should spend 5 minutes or more on each scale Is this correct If not what mistake did he make Then solve for the correct answer
Module 2 79 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
24 Critical Thinking Anika wants to determine the maximum number of tulip bulbs (t) she can purchase if each bulb costs $150 She will also need to purchase separate pots for each bulb at $125 each and a bag of potting soil for $1000 Set up an inequality to determine how many tulip bulbs Anika can purchase without spending more than $2000 and solve it Can Anika buy exactly enough bulbs and pots to spend the full $2000 Explain Can you think of a better inequality to describe the answer
25 Geometry The area of the triangle shown is no more than 10 square inches
a Write an inequality that can be used to find x
b Solve the inequality from part a c What is the maximum height of the triangle
Lesson Performance TaskWhen planning an airplane route the trip planner must be careful to consider the range the aircraft can travel and the availability of airports to stop and refuel
A large commercial jet airplane burns approximately 5 gallons of fuel per mile flown plus about 8500 gallons of fuel per trip to reach cruising altitude With a useable fuel capacity of 50000 gallons (there is additional fuel reserved for emergencies) describe the acceptable distance for which an airline could establish a non-stop flight
For flights originating from Chicago determine which cities could be safely reached by a non-stop flight
City Distance from Chicago (miles)
Bangalore India 8530
Jakarta Indonesia 9810
Johannesburg South Africa 8680
Moscow Russia 4970
Paris France 4130
Perth Australia 10970
Tokyo Japan 6300
copy H
oug
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its copySarych
eva O
lesiaShutterstock
(2x - 3) in
4 in
Module 2 80 Lesson 4
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Name Class Date
Resource Locker
Explore Truth Tables and Compound StatementsA compound statement is formed by combining two or more simple statements A compound statement can be true or false A compound statement involving AND is true when both simple statements are true A compound statement involving OR is true when either one simple statement or both are true
A Complete the truth table
P QP
True or FalseQ
True or FalseP AND Q
True or False
A dog is a mammal Red is a color
A dog is a mammal Red is not a color
A dog is a fish Red is a color
A dog is a fish Red is not a color
B P AND Q is true when
C Complete the truth table
P QP
True or FalseQ
True or FalseP OR Q
True or False
1 is an odd number 2 is an even number
1 is an odd number 2 is an odd number
1 is an even number 2 is an even number
1 is an even number 2 is an odd number
D P OR Q is true when
Reflect
1 Give two simple statements P and Q for which P AND Q is false and P OR Q is true
Module 2 81 Lesson 5
25 Creating and Solving Compound Inequalities
Essential Question How can you solve a compound inequality and graph the solution set
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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Explain 1 Solving Compound Inequalities Involving ANDCombining two or more simple inequalities forms a compound inequality The graph of a compound inequality involving AND is the intersection or the overlapping region of the simple inequality graphs
Compound Inequalities AND
Words Algebra Graph
All real numbers greater than 2AND less than 6
x gt 2 AND x lt 62 lt x lt 6
All real numbers greater than or equal to 2 AND less than or equal to 6
x ge 2 AND x le 62 le x le 6
Example 1 Solve each compound inequality and graph the solutions
A 4 le x + 2 le 8
4 le x + 2 AND x + 2 le 8 Write the compound inequality using AND
4 - 2 le x + 2 - 2 x + 2 - 2 le 8 - 2 Subtract 2 from both sides of each simple inequality
2 le x x le 6 Simplify
Graph 2 le x
Graph x le 6
Graph the intersection by finding where the two graphs overlap
B -5 le 2x + 3 lt 9
-5 - le 2x + 3 - lt 9 - Subtract from each part of the inequality
le 2x lt Simplify
-8 _ le 2x _ lt 6 _ Divide each part of the inequality by
le x lt Simplify
Graph -4 le x
Graph x lt 3
Graph the intersection by finding where the two graphs overlap -1 0 1 2 3 4 5-5-4 -3 -2
0 2 4 6 8 10 12-8-6-4 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 82 Lesson 5
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Reflect
2 Discussion Explain why 2 le x le 6 can be considered the short method for writing the AND compound inequality x ge 2 AND x le 6
YourTurn
Solve each compound inequality and graph the solutions
3 -2 lt x - 3 lt 5
4 -10 lt 3x + 2 le 8
Explain 2 Solving Compound Inequalities Involving ORThe graph of a compound inequality involving OR is the union or the combined region of the simple inequality graphs
Compound Inequalities OR
Words Algebra Graph
All real numbers less than 2OR greater than 6
x lt 2 OR x gt 6
All real numbers less than or equal to 2OR greater than or equal to 6
x le 2 OR x ge 6
-1 0 1 2 3 4 5-5-4 -3 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 83 Lesson 5
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Example 2 Solve each compound inequality and graph the solutions
A -4 + x gt 1 OR -4 + x lt -3
-4 + x gt 1 OR -4 + x lt -3 Write the compound inequality using OR
-4 + 4 + x gt 1 + 4 -4 + 4 + x lt -3 + 4 Add 4 to both sides of each simple inequality
x gt 5 x lt 1 Simplify
Graph x gt 5
Graph x lt 1
Graph the union by combining the graphs
B 2x le 6 OR 3x gt 12
2x le 6 OR 3x gt 12 Write the compound inequality using OR
2x _ le 6 _ OR 3x _ gt 12 _ Divide the first simple inequality by
x le OR x gt
Graph x le 3
Graph x gt 4
Graph the union by combining the graphs
Reflect
5 Critical Thinking What kind of compound inequality has no solution
Divide the second simple inequality by
Simplify
0 1 2 3 4 5 6-4 -3 -2 -1
-0 1 2 3 4 5 6-4 -3 -2 -1
Module 2 84 Lesson 5
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oug
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Your Turn
Solve each compound inequality and graph the solutions
6 x - 5 ge -2 OR x -5 le -6
7 4x -1 lt 15 OR 8x ge 48
Explain 3 Creating Compound Inequalities From GraphsGiven a number line graph with a solution set graphed you can create a compound inequality to fit the graph
Example 3 Write the compound inequality shown by each graph
A
The shaded portion of the graph is not between two values so the compound inequality involves OR
On the left the graph shows an arrow pointing left from -1 and a solid circle so use le
The inequality is x le -1
On the right the graph shows an arrow pointing right from 7 and a solid circle so use ge
The inequality is x ge 7
The compound inequality is x le -1 OR x ge 7
B
The graph is shaded between the values and so the compound inequality involves AND
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The compound inequality is
-1 0 1 2 3 4 5-5-4 -3 -2
4 5 6 7 8 9 100 1 2 3
2 3 4 5 6 7 8-2 -1 0 1
10 2 3 4 5 6 7 8 9-1
Module 2 85 Lesson 5
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oug
hton Mifflin H
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pany
Reflect
8 What is a short method to write the compound inequality x ge 0 AND x lt 6
Your Turn
Write the compound inequality shown by each graph
9
10
Explain 4 Expressing Acceptable Levels with Compound Inequalities
You can express quality-controls levels in real-world problems using compound inequalities
Example 4 Write a compound inequality to represent the indicated quality-control level and graph the solutions
A The recommended pH level for swimming pool water is between 72 and 76 inclusive
Let p be the pH level of swimming pool water
72 is less than or equal to pH level is less than or equal to 76
72 le p le 76
The compound inequality is 72 le p le 76
Graph the solutions
0-10 -8-9 -7-6 -5-4 -3 -2 -1
71 72 73 74 75 76 77 78 79 8070
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 86 Lesson 5
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oug
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B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
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oug
hton Mifflin H
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pany
bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
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oug
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cour
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Com
pan
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Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
arcourt Publishin
g Com
pany bull Im
age C
redits copy
Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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Mif
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cour
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Com
pan
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mag
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bik
erid
erlo
nd
onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
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The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
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oug
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Explain 3 Modeling Expressions in ContextThe table shows some words and phrases associated with the four basic arithmetic operations These words and phrases can help you translate a real-world situation into an algebraic expression
Operation Words Examples
Addition the sum of added to plus more than increased by total altogether and
1 A number increased by 22 The sum of n and 23 n + 2
Subtraction less than minus subtracted from the difference of take away taken from reduced by
1 The difference of a number and 22 2 less than a number3 n - 2
Multiplication times multiplied by the product of percent of
1 The product of 06 and a number2 60 of a number3 06n
Division divided by division of quotient of divided into ratio of
1 The quotient of a number and 52 A number divided by 53 n divide 5 or n __ 5
Example 3 Write an algebraic expression to model the given context Give your answer in simplest form
the price of an item plus 6 sales tax
Price of an item + 6 sales tax
p + 006p
The algebraic expression is p + 006p or 106p
the price of a car plus 85 sales tax
The price of a car +
+
The algebraic expression is
or
Reflect
7 Use the Distributive Property to show why p + 006p = 106p
8 What could the expression 3(p + 006p) represent Explain
Your Turn
Write an algebraic expression to model the given context Give your answer in simplest form
9 the number of gallons of water in a tank that already has 300 gallons in it after being filled at 35 gallons per minute for m minutes
10 the original price p of an item less a discount of 15
Module 2 48 Lesson 1
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oug
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cour
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Elaborate
11 When given an algebraic expression involving subtraction why is it best to rewrite the expression using addition before identifying the terms
12 How do you interpret algebraic expressions in terms of their context
13 How do you simplify algebraic expressions
14 Essential Question Check In How do you write algebraic expressions to model quantities
bull Online Homeworkbull Hints and Helpbull Extra Practice
Evaluate Homework and PracticeIdentify the terms and the coefficients of the expression
1 -20 + 5p - 7z 2 8x - 20y - 10
Identify the factors of the terms of the expression
3 5 + 6a + 11b 4 13m - 2n
5 Erin is buying produce at a store She buys c cucumbers at $099 each and a apples at $079 each What does the expression 099c + 079a represent
6 The number of bees that visit a plant is 500 times the number of years the plant is alive where t represents the number of years the plant is alive What does the expression 500t represent
Evaluate Homework and Practice
Module 2 49 Lesson 1
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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oug
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Leonard
LenzC
orbis
7 Lorenzo buys 3 shirts at s dollars apiece and 2 pairs of pants at p dollars a pair What does the expression 3s + 2p represent
8 If a car travels at a speed of 25 mih for t hours then travels 45 mih for m hours what does the expression 25t + 45m represent
9 The price of a sandwich is $150 more than the price of a smoothie which is d dollars What does the expression d + 15 represent
10 A bicyclist travels 1 mile in 5 minutes If m represents minutes what does the expression m __ 5 represent
11 What are the factors of the expression (y - 2)(x + 3)
12 Explain the Error A student wrote that there are two terms in the expression 3p - (7 - 4q) Explain the studentrsquos error
13 Yolanda is buying supplies for school She buys n packages of pencils at $140 per package and m pads of paper at $120 each What does each term in the expression 14n + 12m represent What does the entire expression represent
14 Chris buys p pairs of pants and 4 more shirts than pairs of pants Shirts cost $18 each and pair of pants cost $25 each What does each term in the expression 25p + 18(p + 4) represent What does the entire expression represent
Module 2 50 Lesson 1
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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ssie
W
alke
rLi
ved
In Im
ages
Cor
bis
Suppose a and b give the populations of two states where a gt b Compare the expressions and tell which of the given pair is greater or if the expressions are equal
15 b _ a + b
and 05
16 a + 13c and b + 13c where c is the population of a third state
17 a - b _ 2 and a - b _ 2
18 a + b and 2b
19 5(a + b) and (a + b)5
Write an algebraic expression to model the given context Give your answer in simplest form
20 the price s of a pair of shoes plus 5 sales tax 21 the original price p of an item less a discount of 20
22 the price h of a recently bought house plus 10 property tax
23 the principal amount P originally deposited in a bank account plus 03 interest
Module 2 51 Lesson 1
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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arcourt Publishin
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pany
24 Match each statement with the algebraic expression that models it
A the price of a winter coat and a 20 discount x + 002x = 102x
B the base salary of an employee and a 2 salary increase x - 020x = 080x
C the cost of groceries and a 2 discount with coupons x + 020x = 120x
D the number of students attending school last year and a 20 increase from last year x - 002x = 098x
HOT Focus on Higher Order Thinking
25 Critique Reasoning A student is given the rectangle and the square shown The student states that the two figures have the same perimeter Is the student correct Explain your reasoning
26 Multi-Step Yon buys tickets to a concert for himself and a friend There is a tax of 6 on the price of the tickets and an additional booking fee of $20 for the transaction Write an algebraic expression to represent the price per person Simplify the expression if possible
x + 2
x + 2x
x + 4
Module 2 52 Lesson 1
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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Com
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27 Persevere in Problem Solving Jerry is planting white daisies and red tulips in his garden and he wants to choose a pattern in which the tulips surround the daisies He uses tiles to generate patterns starting with two rows of three daisies He surrounds these daisies with a border of tulips The design continues as shown
a Jerry writes the expression 8(b - 1) + 10 for the number of tulips in each border wherein b is the border number and b ge 1 Explain why Jerryrsquos expression is correct
b Elaine wants to start with two rows of four daisies Her reasoning is that Jerry started with two rows of three daisies and his expression was 8(b - 1) + 10 so if she starts with two rows of four daisies her expression will be 10(b - 1) + 10 Is Elainersquos statement correct Explain
Border 1 Border 2 Border 3
Module 2 53 Lesson 1
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
Lesson Performance Task
Becky and Michele are both shopping for a new car at two different dealerships Dealership A is offering $500 cash back on any purchase while Dealership B is offering $1000 cash back The tax rate is 5 at Dealership A but 8 at Dealership B Becky wants to buy a car that is $15000 and Michele is planning to buy a car that costs $20000 Use algebraic expressions to help you answer the following questions
a At which dealership will Becky get the better deal How much does she save
b At which dealership will Michele get the better deal How much does she save
c What generalization can you make that would help any shopper know which dealership has the better deal [Hint At what price point would the two deals be equal]
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oug
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Tom G
rillC
orbis
Module 2 54 Lesson 1
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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pan
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Name Class Date
Resource Locker
Explore Creating Equations from Verbal Descriptions
You can use what you know about writing algebraic expressions to write an equation that represents a real-world situation
Suppose Cory and his friend Walter go to a movie Each of their tickets costs the same amount and they share a frozen yogurt that costs $550 The total amount they spend is $1990 How can you write an equation that describes the situation
A Identify the important information
The word tells you that the relationship describes an equation
The word total tells you that the operation involved in the relationship is
What numerical information do you have
What is the unknown quantity
B Write a verbal description
Choose a name for the variable In this case use c for
The verbal description is Twice the cost of plus the cost
of equals
C To write an equation write a numerical or expression for each quantity
and insert an equal sign in the appropriate place An equation is
Reflect
1 How can you use a verbal model to write an equation for the situation described
Module 2 55 Lesson 2
22 Creating and Solving EquationsEssential Question How do you use an equation to model and solve a real-world problem
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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arcourt Publishin
g Com
pany bull Im
age C
redits D
igital
Vision
Getty Im
ages
2 Could you write a different equation to describe the situation Explain your reasoning
Explain 1 Creating and Solving Equations Involving the Distributive Property
When you create an equation to model a real-world problem your equation may involve the Distributive Property When you solve a real-world problem you should always check that your answer makes sense
Example 1 Write and solve an equation to solve each problem
A Aaron and Alice are bowling Alicersquos score is twice the difference of Aaronrsquos score and 5 The sum of their scores is 320 Find each studentrsquos bowling score
Write a verbal description of the basic situation
The sum of Aaronrsquos score and Alicersquos score is 320
Choose a variable for the unknown quantity and write an equation to model the detailed situation
Let a represent Aaronrsquos score Then 2 (a - 5) represents Alicersquos score
a + 2 (a - 5) = 320
Solve the equation for a
a + 2 (a - 5) = 320
a + 2a - 10 = 320 Distributive Property
3a - 10 = 320
3a - 10 + 10 = 320 + 10 Addition Property of Equality
3a = 330
3a _ 3 = 330 _ 3 Division Property of Equality
a = 110
So Aaronrsquos score is 110 and Alicersquos score is 2 (a - 5) = 2 (110 - 5) = 2 (105) = 210
Check that the answer makes sense
110 + 210 = 320 so the answer makes sense
B Mari Carlos and Amanda collect stamps Carlos has five more stamps than Mari and Amanda has three times as many stamps as Carlos Altogether they have 100 stamps Find the number of stamps each person has
Write a verbal description of the basic situation
Module 2 56 Lesson 2
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Choose a variable for the unknown quantity and write an equation to model the detailed situation
Let s represent the number of stamps Mari has Then Carlos has stamps
and Amanda has stamps
s + + 3 ( ) =
Solve the equation for s
s + + 3 ( ) =
s + s + 5 + 3s + = Distributive Property
+ = Combine like terms
s = Subtraction Property of Equality
s = Division Property of Equality
So Mari has stamps Carlos has stamps and Amanda
has stamps
Check that the answer makes sense
+ + = the answer makes sense
=
Reflect
3 Would a fractional answer make sense in this situation
4 Discussion What might it mean if a check revealed that the answer to a real-world problem did not make sense
Module 2 57 Lesson 2
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Your Turn
Write and solve an equation to solve the problem
5 A rectangular garden is fenced on all sides with 256 feet of fencing The garden is 8 feet longer than it is wide Find the length and width of the garden
Explain 2 Creating and Solving Equations with Variables on Both Sides
In some equations variables appear on both sides You can use the properties of equality to collect the variable terms so that they all appear on one side of the equation
Example 2 Write and solve an equation to solve each problem
A Janine has job offers at two companies One company offers a starting salary of $28000 with a raise of $3000 each year The other company offers a starting salary of $36000 with a raise of $2000 each year In how many years would Janinersquos salary be the same with both companies What will the salary be
Write a verbal description of the basic situation
Let n represent the number of years it takes for the salaries to be equal
Base Salary A plus $3000 per year raise = Base Salary B + $2000 per year raise
28000 + 3000n = 36000 + 2000n
28000 + 3000n - 2000n = 36000 + 2000n - 2000n Subtraction Property of Equality
28000 + 1000n = 36000 Combine like terms
28000 + 1000n - 28000 = 36000 - 28000 Subtraction Property of Equality
1000n = 8000 1000n _ 1000 = 8000 _ 1000 Division Property of Equality
n = 8
28000 + 3000 (8) = 36000 + 2000 (8)
52000 = 52000
In 8 years the salaries offered by both companies will be $52000
(w + 8) feet
w feet
Module 2 58 Lesson 2
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B One moving company charges $800 plus $16 per hour Another moving company charges $720 plus $21 per hour At what number of hours will the charge by both companies be the same What is the charge
Write a verbal description of the basic situation Let t represent the number of hours that the move takes
Moving Charge A plus $16 per hour = Moving Charge B plus $21 per hour
800 + t = 720 + t
800 + t - t = 720 + t - t Subtraction Property of Equality
800 = 720 + t
800 - 720 = 720 + t - 720 Subtraction Property of Equality
= t
_ = t _
Division Property of Equality
t =
The charges are the same for a job that takes hours
Substitute the value 16 in the original equation
800 + 16t = 720 + 21t
800 + 16 ( ) = 720 + 21 ( ) 800 + = 720 +
=
After hours the moving charge for both companies will be
Reflect
6 Suppose you collected the variable terms on the other side of the equal sign to solve the equation Would that affect the solution
Module 2 59 Lesson 2
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Your Turn
Write and solve an equation to solve each problem7 Claire bought just enough fencing to enclose either a
rectangular garden or a triangular garden as shown The two gardens have the same perimeter How many feet of fencing did she buy
8 A veterinarian is changing the diets of two animals Simba and Cuddles Simba currently consumes 1200 Calories per day That number will increase by 100 Calories each day Cuddles currently consumes 3230 Calories a day That number will decrease by 190 Calories each day The patterns will continue until both animals are consuming the same number of Calories each day In how many days will that be How many Calories will each animal be consuming each day then
Explain 3 Constructing Equations from an Organized TableYou can use a table to organize information and see relationships
Example 3 Construct and solve an equation to solve the problem
Kim works 4 hours more each day than Jill does and Jack works 2 hours less each day than Jill does Over 2 days the number of hours Kim works is equal to the difference of 4 times the number of hours Jack works and the number of hours Jill works How many hours does each person work each day
Analyze Information
Identify the important information
bull Kim works hours more per day than Jill does
bull Jack works hours less per day than Jill does
Formulate a Plan
Make a table using the information given Let x be the number of hours Jill works in one day
Hours Worked Per Day Hours Worked Over 2 Days
Kim
Jill
Jack
Over 2 days the number of hours Kim works is equal to the difference of 4 times the number of hours Jack works and the number of hours Jill works
(3x - 3)(x - 3)
(2x - 1) (2x - 1)
2x
Module 2 60 Lesson 2
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Solve
2 (x + 4) = 4 2 (x - 2) - 2x
2 (x + 4) = (x - 2) - 2x Simplify
2x + = 8x - - 2x Distributive Property
2x + 8 = x - 16
2x + 8 + = 6x - 16 + Addition Property of Equality
2x + = 6x
2x + 24 - x = 6x - x Subtraction Property of Equality
24 = x
24 _ = x _ Division Property of Equality
= x
Jill works hours per day Kim works hours per day and Jack works
hours per day
Justify and Evaluate
Substitute x = 6 into the original equation
2 (6 + 4) = 4 2 (6 - 2) - 2x
2 ( ) = 8 ( ) - 2 ( ) =
Your Turn
Write and solve an equation to solve the problem
9 Lisa is 10 centimeters taller than her friend Ian Ian is 14 centimeters taller than Jim Every month their heights increase by 2 centimeters In 7 months the sum of Ianrsquos and Jimrsquos heights will be 170 centimeters more than Lisarsquos height How tall is Ian now
Height now Height after 7 months
Module 2 61 Lesson 2
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Elaborate
10 How can you use properties to solve equations with variables on both sides
11 How is a table helpful when constructing equations
12 When solving a real-world problem to find a personrsquos age would a negative solution make sense Explain
13 Essential Question Check-In How do you write an equation to represent a real-world situation
bull Online Homeworkbull Hints and Helpbull Extra Practice
Write an equation for each description
1 The sum of 14 and a number is equal to 17 2 A number increased by 10 is 114
3 The difference between a number and 12 is 20 4 Ten times the sum of half a number and 6 is 8
5 Two-thirds a number plus 4 is 7 6 Tanmayi wants to raise $175 for a school fundraiser She has raised $120 so far How much more does she need to reach her goal
7 Hector is visiting a cousin who lives 350 miles away He has driven 90 miles How many more miles does he need to drive to reach his cousinrsquos home
8 The length of a rectangle is twice its width The perimeter of the rectangle is 126 feet
Evaluate Homework and Practice
Module 2 62 Lesson 2
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cour
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pan
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(t)copy
Pete
r K
imS
hutt
erst
ock
Write and solve an equation for each situation
9 In one baseball season Peter hit twice the difference of the number of home runs Alice hit and 6 Altogether they hit 18 home runs How many home runs did each player hit that season
10 The perimeter of a parallelogram is 72 meters The width of the parallelogram is 4 meters less than its length Find the length and the width of the parallelogram
11 One month Ruby worked 6 hours more than Isaac and Svetlana worked 4 times as many hours as Ruby Together they worked 126 hours Find the number of hours each person worked
12 In one day Annie traveled 5 times the sum of the number of hours Brian traveled and 2 Together they traveled 20 hours Find the number of hours each person traveled
13 Xian and his cousin Kai both collect stamps Xian has 56 stamps and Kai has 80 stamps The boys recently joined different stamp-collecting clubs Xianrsquos club will send him 12 new stamps per month Kairsquos club will send him 8 new stamps per month After how many months will Xian and Kai have the same number of stamps How many stamps will each have
14 Kenya plans to make a down payment plus monthly payments in order to buy a motorcycle At one dealer she would pay $2500 down and $150 each month At another dealer she would pay $3000 down and $125 each month After how many months would the total amount paid be the same for both dealers What would that amount be
ℓ meters
(ℓ - 4) meters
Module 2 63 Lesson 2
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oug
hton Mifflin H
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pany
15 Community Gym charges a $50 membership fee and a $55 monthly fee Workout Gym charges a $200 membership fee and a $45 monthly fee After how many months will the total amount of money paid to both gyms be the same What will the amount be
16 Tina is saving to buy a notebook computer She has two options The first option is to put $200 away initially and save $10 every month The second option is to put $100 away initially and save $30 every month After how many months would Tina save the same amount using either option How much would she save with either option
Use the table to answer each question
Starting Salary Yearly Salary Increase
Company A $24000 $3000
Company B $30000 $2400
Company C $36000 $2000
17 After how many years are the salaries offered by Company A and Company B the same
18 After how many years are the salaries offered by Company B and Company C the same
19 Paul started work at Company B ten years ago at the salary shown in the table At the same time Sharla started at Company C at the salary shown in the table Who earned more during the last year How much more
20 Georgersquos page contains twice as many typed words as Billrsquos page and Billrsquos page contains 50 fewer words than Charliersquos page If each person can type 60 words per minute after one minute the difference between twice the number of words on Billrsquos page and the number of words on Charliersquos page is 210 How many words did Billrsquos page contain initially Use a table to organize the information
Initial number of words
Total number of words after one minute
Module 2 64 Lesson 2
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oug
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cour
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pan
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21 Geometry Sammie bought just enough fencing to border either a rectangular plot or a square plot as shown The perimeters of the plots are the same How many meters of fencing did she buy
HOT Focus on Higher Order Thinking
22 Justify Reasoning Suppose you want to solve the equation 2a + b = 2a where a and b are nonzero real numbers Describe the solution to this equation Justify your description
23 Multi-step A patio in the shape of a rectangle is fenced on all sides with 134 feet of fencing The patio is 5 feet less wide than it is long
a What information can be used to solve the problem How can you find the information
b Describe how to find the area of the patio What is the area of the patio
24 Explain the Error Kevin and Brittany write an equation to represent the following relationship and both students solve their equation Who found the correct equation and solution Why is the other person incorrect
5 times the difference of a number and 20 is the same as half the sum of 4 more than 4 times a number
Kevin Brittany
5 (x - 20) = 1 _ 2 (4x + 4) 5 (20 + x) = 1 _ 2 (4x + 4)
5x - 100 = 2x + 2 100 - 5x = 2x + 2
3x - 100 = 2 100 - 7x = 2
3x = 102 -7x = -98
x = 34 x = 14
(3x + 2) meters
(x + 2) meters
(x + 2) meters
(x - 1) meters
ℓ feet
(ℓ - 5) feet
Module 2 65 Lesson 2
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oug
hton Mifflin H
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25 What If Alexa and Zack are solving the following problem
The number of miles on Car A is 50 miles more than the number of miles on Car B and the number of miles on Car B is 30 miles more than the number of miles on Car C All the cars travel 50 miles in 1 hour After 1 hour twice the number of miles on Car A is 70 miles less than 3 times the number of miles on Car C How many miles were there on Car B initially
Alexa assumes there are m miles on Car B Zack assumes there are m miles on Car C Will Zackrsquos answer be the same as Alexarsquos answer Explain
Lesson Performance Task
Stacy Oliver and Jivesh each plan to put a certain amount of money into their savings accounts that earn simple interest of 6 per year Stacy puts $550 more than Jivesh and Oliver puts in 2 times as much as Jivesh After a year the amount in Stacyrsquos account is 2 times the sum of $212 and the amount in Oliverrsquos account How much does each person initially put into his or her account Who had the most money in his or her account after a year Who had the least Explain
Zackrsquos Table Initial Miles
Miles after One Hour
Alexarsquos Table Initial Miles
Miles after One Hour
Amount in Account Initially Amount in Account after One Year
Module 2 66 Lesson 2
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oug
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cour
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pan
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Name Class Date
Resource Locker
Explore Rearranging Mathematical FormulasLiteral Equations are equations that contain two or more variables There are many literal equations in the form of math science and engineering formulas These formulas may seem like they can only be solved for the variable that is isolated on one side of the formula By using inverse operations and the properties of equality a formula can be rearranged so any variable in the formula can be isolated It is no different than how equations are solved by using inverse operations and the properties of equality
How can you solve the equation 42 = 6x
A42 _ = 6x _ What is the reason for dividing
Why divide by
= x By rearranging the equation x was isolated and the solution was found
The mathematical formula for the volume of a rectangular prism B = Vh or V = ℓwh is a literal equation V represents volume ℓ represents length w represents width and h represents height Using inverse operations the formula can be rearranged to solve for any one of the variables that might be unknown Like solving for x a formula can be rearranged to isolate a variable
B In the formula V = ℓwh the variable h needs to be isolated
The operation of is used in the formula The inverse
operation should be used
to isolate
C V _____ = ℓwh _____
V _ =
The formula rearranged in this way can easily produce the height of the rectangular prism when the volume length and width are known
Reflect
1 Using the formula for a rectangular prism rewrite the formula to solve for ℓ
ℓw
h
Module 2 67 Lesson 3
23 Solving for a VariableEssential Question How do you rewrite formulas and literal equations
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hyAurora Ph
otosCorb
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Explain 1 Rearranging Scientific FormulasUse inverse operations to isolate the unknown variable in a scientific formula
The formula for density is D = m __ V Lead has a very high density of 11340 kg m 3 Plastic foam has a very low density of 75 kg m 3 The formula for density can be rearranged to solve for V volume or m mass
Example 1
A A sinker on a fishing line is made of lead and has a volume of 0000015 m 3 What is the mass of the sinker
The density formula can be rearranged to isolate m the mass The values for volume and density can then be substituted into the formula to find the mass
D = m _ V
DV = ( m _ V ) V DV = m
(11340 kg m 3 ) (0000015 m 3 ) = m
017 kg asymp m
B The design for a life preserver requires 03 kilogram of plastic foam to provide proper buoyancy What is the volume of the plastic foam required
Rearrange the density formula to isolate V
D = m _ V
(D) V = m _ V
DV =
DV _ = m _
V =
Now substitute the given values
V = _
V = m 3
Your Turn
2 For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Determine the altitude in feet when t is -275 ∘F and g is 60 ∘F
Module 2 68 Lesson 3
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Explain 2 Rearranging Literal EquationsUsing inverse operations to rearrange literal equations can be applied to any formula The interest formula I = prt is another example of a literal equation In the formula I represents interest p the principal or the initial amount to which interest will be applied r the rate at which interest will be paid and t is the time in years
Example 2
A Find the number of years used in the calculation of a $1000 loan at an interest rate of 5 with interest totaling $600
Solve the formula for t
I = prt
I _ pr = prt
_ pr
I _ pr = t
Substitute the given values Since the interest rate is 5 r = 005$600 __
$1000 middot 005 = t
12 = t
So the length of time for the loan is 12 years
B Determine the interest rate for a $2000 loan that will be paid off in 4 years with interest totaling $640 In order to find the interest rate solve the formula for r
I = prt
I _ = prt _
_ = r
Now substitute the values and simplify
__
( ) ( ) = r
008 = r
So the interest rate is per year
Your Turn
3 The formula y = mx + b is the slope-intercept form of the equation of a line Solve the equation for m
Module 2 69 Lesson 3
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bull Online Homeworkbull Hints and Helpbull Extra Practice
Solve for the indicated variable in each mathematical formula
1 C = 2πr for r 2 A = 1 __ 2 bh for b 3 y = mx + b for x
4 A = 1 __ 2 (a + b)h for h 5 V = πr2h for h 6 SA = 2πr2 + 2πrh for h
Solve for the indicated variable in each scientific formula
7 d = rt for t 8 PV = nRT for T
9 A = FV - OV _______ T for OV 10 C = Wtc _ 1000 for W
Evaluate Homework and Practice
Elaborate
4 Discussion What could be a reason for isolating a variable in a literal equation
5 Describe a situation in which a formula could be used more easily if it were rearranged Include the formula in your description
6 Essential Question Check-In How do you isolate a variable
Module 2 70 Lesson 3
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Mif
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cour
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mag
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cean
C
orb
is
Solve for the indicated variable in each literal equation
11 2p + 5r = q for p 12 -10 = xy + z for x 13 a __ b = c for b
14 h - 4 _ j = k for j 15 x __ 5 - g = a for x 16 5p + 9c = p for c
17 2 __ 5 (z + 1) = y for z 18 g (h + 2 __ 3 ) = 1 for h 19 a(n - 3) + 8 = bn for n
20 Which is a possible way to rewrite the equation y = 3x + 3b to solve for b
A b = y - 3x
_ 3 C b = y - 3
_____ 3x
B b = 3(y - 3x) D b = x(y - 3)
21 Sports To find a baseball pitcherrsquos earned run average (ERA) you can use the formula Ei = 9r in which E represents ERA i represents the number of innings pitched and r represents the number of earned runs allowed Solve the equation for E What is a pitcherrsquos ERA if he allows 5 earned runs in 18 innings pitched
22 Meteorology For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Solve the equation for a If the atmospheric temperature is -655 ∘F and the ground temperature is 57 ∘F what is the altitude
Module 2 71 Lesson 3
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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arcourt Publishin
g Com
pany bull Im
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Rand
y D
uch
aineA
lamy
HOT Focus on Higher Order Thinking
23 Explain the Error A student was asked to use the formula for the perimeter of a rectangle P = 2ℓ + 2w to solve for ℓ The student came up with an answer P - 2w = 2ℓ What error did the student make Explain Then solve for ℓ
24 Multi-Step The formula c = 5p + 215 relates c the total cost in dollars of hosting a birthday party at a skating rink to p the number of people attending If Alliersquos parents are willing to spend $300 for a party how many people can attend
25 Multi-Step The formula for the area of a triangle is A = 1 __ 2 bh in which b represents the length of thebase and h represents the height If a triangle has an area of 192 mm2 and the height is 12 mm what is the measure of the base
Lesson Performance TaskThe following table shows the average low temperatures in Fahrenheit for the city of Boston for several months during the year The formula F = 9 __ 5 C + 32 allows you to determine the temperature in Fahrenheit when given the temperature in Celsius
MonthTemperature in
FahrenheitTemperature in
Celsius
January 22deg
April 41deg
July 65deg
October 47deg
December 28deg
a Use the information given to determine the average low temperatures in Celsius
b Would it ever be possible for the temperature in Celsius to have a greater value than the temperature in Fahrenheit Explain why or why not
Module 2 72 Lesson 3
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
Name Class Date
Resource Locker
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oug
hton
Mif
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Har
cour
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Com
pan
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mag
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edit
s copy
Patr
ick
Lan
eSo
mos
Imag
esC
orb
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Explore Creating Inequalities from Verbal DescriptionsAn inequality is a statement that compares two expressions that are not strictly equal by using one of the following inequality signs
Symbol Meaning
lt is less than
le is less than or equal to
gt is greater than
ge is greater than or equal to
ne is not equal to
You have probably seen a sign at an amusement park saying something like ldquoYou must be at least 48 inches tall to ride this riderdquo This statement could be written as h ge 48 in where h represents the height of a person allowed to ride
Nora is planning a birthday party for her little sister Colleen Norarsquos budget will allow her to spend no more than $50 for party supplies Eight children including Colleen will attend the party and Nora wants to determine how much she could spend on party favors for each child She will also purchase a cake for $10 Write an inequality that represents the situation and find possible solutions
A First let c represent the cost of a party favor for each child Write an expression for the total cost of the party as a function of c
c +
B Which inequality symbol should be used to represent the phrase ldquono more thanrdquo
C Write the inequality that represents Norarsquos budget goal
8c + 10 le
D Suppose Nora finds party favors that cost $4 each Use a value of 4 for c and check to see if this inequality is true
8 middot 4 + 10 le 50
le 50
Module 2 73 Lesson 4
24 Creating and Solving Inequalities
Essential Question How do you write and solve an inequality that represents a real-world situation
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
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pany
Is the inequality true
Could Nora buy $6 party favors for all of her guests without going over budget
Reflect
1 Why does an inequality represent Norarsquos budget calculation better than an equation
2 The solution set of an inequality consists of all values that make the statement true Describe the whole dollar amounts that are in the solution set for this situation
Explain 1 Creating and Solving Inequalities Involving the Distributive Property
You may need to use the Distributive Property before you can solve an inequality
Distributive Property If a b and c are real numbers then a(b + c) = ab + ac
The inequality sign must be reversed when multiplying or dividing both sides of an inequality by a negative number
Example 1
A Trina is buying 12 shirts for the drama club She will choose a style for the blank shirts and then pay an additional charge of $275 for each shirt to have the club logo If Trina cannot spend more than $99 how much can she spend on each blank shirt Write and solve an inequality to find the possible cost of each blank shirt
Let s represent the cost of each blank shirt
Write an inequality to represent the situation 12(s + 275) le 99
Use the Distributive Property 12s + 33 le 99
Subtraction Property of Inequality 12s + 33 - 33 le 99 - 33
Simplify 12s le 66
Division Property of Inequality 12s ___ 12 le 66 __ 12
Simplify s le 55
Module 2 74 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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oug
hton
Mif
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Har
cour
t Pub
lishi
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Com
pan
y
Check your answer
Since s le 55 check a smaller number 12(5 + 275) le 99
Trina can order blank shirts that cost $550 or less 93 le 99 true
B Sergio needs to buy gifts for 8 friends He wants to give the same gift to all his friends and he plans to have the gifts wrapped for an additional charge of $150 each If Sergio spends at least $70 he will receive free shipping on his order Write and solve an inequality to determine how much Sergio needs to spend on each gift in order to receive free shipping
Let g be the cost of one gift
Write an inequality to represent the situation ( g + ) ge 70
Use the Distributive Property g + ge 70
Subtraction Property of Inequality g + 12 - ge 70 -
Simplify 8g ge
Division Property of Inequality 8g _
ge 58 _
Simplify g ge
Check your answer
Since g ge 725 check a larger number 8(8 + 150) ge 70
Sergio must spend at least on each gift ge 70
Reflect
3 Discussion Why is the first step in solving the inequality to use the Distributive Property instead of working inside the parentheses
Your Turn
4 Zachary is planning to send a video game to each of his two brothers If he buys the same game for both brothers and pays $475 to ship each game how much can he spend on each game without spending more than $100 Write and solve an inequality for this situation
Solve each inequality
5 4 _ 3 (6x + 9) lt 4 6 -2 ( 1 _ 4 x + 2 ) ge 5
Module 2 75 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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arcourt Publishin
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pany
Explain 2 Creating and Solving Inequalities with Variables on Both Sides
Some inequalities have variable terms on both sides of the inequality symbol You can solve these inequalities the same way you solved equations with variables on both sides Use the properties of inequality to collect all the variable terms on one side and all the constant terms on the other side
Example 2
A The Daily Info charges a fee of $650 plus $80 per week to run an ad The Peoplersquos Paper charges $145 per week For how many weeks must an ad run for the total cost at the Daily Info to be less expensive than the cost at the Peoplersquos Paper Let w be the number of weeks the ad runs in the paper
Write an inequality to represent the situation 650 + 80w lt 145w
Subtraction Property of Inequality 650 + 80w - 80w lt 145w - 80w
Simplify 650 lt 65w
Division Property of Inequality 650 _ 65 lt 65w _ 65
Simplify 10 lt w
The total cost at the Daily Info is less than the cost at the Peoplersquos Paper if the ad runs for more than 10 weeks
B The Home Cleaning Company charges $312 to power-wash the siding of a house plus $12 for each window Power Clean charges $36 per window and the price includes power-washing the siding How many windows must a house have to make the total cost from The Home Cleaning Company less expensive than Power Clean Let w be the number of windows
Write an inequality to represent the situation +12w lt 36w
Subtraction Property of Inequality 312 + 12w - lt 36w -
Simplify 312 lt
Division Property of Inequality 312 _ lt 24w _
Simplify lt w
A house must have more than 13 windows for The Home Cleaning Company to be less expensive than Power Clean
Reflect
7 How would the final inequality change if you divided by ndash24 in the next to last step
Your Turn
8 The school band will sell pizzas to raise money for new uniforms The supplier charges $100 plus $4 per pizza The band members sell the pizzas for $7 each Write and solve an inequality to find how many pizzas the band members will have to sell to make a profit
Module 2 76 Lesson 4
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Elaborate
9 Which inequality symbol would you use to represent the following words or phrases Can you come up with more examples
a at most b farther than c younger than d up to
10 Discussion How are the steps to solving an inequality similar to those for solving an equation How are they different
11 Essential Question Check-In How can you write an inequality that represents a real-world situation
Write an inequality that represents the description and then solve
1 Max has more than 5 carrots (number of carrots Max has = c)
2 Brigitte is shorter than 5 feet (Brigittersquos height = h)
3 Twice a number (x) is less than 10 4 Six more than five times a number (x) is at least twenty-one
5 Dave has $15 to spend on an $8 book and two birthday cards (c) for his friends How much can he spend on each card if he buys the same card for each friend
6 Toni can carry up to 18 lb in her backpack Her lunch weighs 1 lb her gym clothes weigh 2 lb and her books (b) weigh 3 lb each How many books can she carry in her backpack
Evaluate Homework and Practice
bull Online Homeworkbull Hints and Helpbull Extra Practice
Module 2 77 Lesson 4
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pany
Solve each inequality
7 3 (x - 2) gt -3 8 5 + 5 (x + 4) le 20 9 3 + 1 _ 2 (3 - x) lt -7
10 3 (x + 6) - 2 (x + 2) ge 10 11 5 (3 - x) -4 (2 - 3x) gt 2 12 1 _ 2 (4x - 2) - 2 _ 3 (6x + 9) le 4
13 x + 1 gt -5 (7 - 2x) 14 5 _ 3 (6x + 3) le 2x - 7
15 2x le - 2 __ 3 (4x + 4) 16 1 __ 2 (-2x - 10) gt 3 (4 - 6x)
17 -5 - 3x ge 2 (10 + 2x) + 3 18 -3 (9x + 20) ge 15x - 20
19 8 ( 1 _ 4 x - 3) + 24 lt 4 ( x + 5 ) 20 6x - 2 (x + 2) gt 2 - 3 (x + 3)
Module 2 78 Lesson 4
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21 Physics A crane cable can support a maximum load of 15000 kg If a bucket has a mass of 2000 kg and gravel has a mass of 1500 kg for every cubic meter how many cubic meters of gravel (g) can be safely lifted by the crane
22 Find the solution set of each inequality below and then determine which inequalities have the same solution set as 1 _ 3 ( -5x - 3 ) lt 14
a 1 _ 3 (5x + 3) gt -14 b 2 _ 5 (10x + 20) gt 44
c - 2 _ 5 (10x + 20) lt -44 d - 1 _ 3 (5x + 3) lt 14
e 2 _ 5 (10x - 20) gt -44 f 1 _ 3 (5x + 3) lt -14
HOT Focus on Higher Order Thinking
23 Explain the Error Sven is trying to find the maximum amount of time he can spend practicing the five scales of piano music he is supposed to be working on He has 60 minutes to practice piano and would like to spend at least 35 minutes playing songs instead of practicing scales So Sven sets up the following inequality where t is the number of minutes he spends on each scale and solves it
60 - 5t le 35-5t le -25
t ge 5
Sven has concluded that he should spend 5 minutes or more on each scale Is this correct If not what mistake did he make Then solve for the correct answer
Module 2 79 Lesson 4
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24 Critical Thinking Anika wants to determine the maximum number of tulip bulbs (t) she can purchase if each bulb costs $150 She will also need to purchase separate pots for each bulb at $125 each and a bag of potting soil for $1000 Set up an inequality to determine how many tulip bulbs Anika can purchase without spending more than $2000 and solve it Can Anika buy exactly enough bulbs and pots to spend the full $2000 Explain Can you think of a better inequality to describe the answer
25 Geometry The area of the triangle shown is no more than 10 square inches
a Write an inequality that can be used to find x
b Solve the inequality from part a c What is the maximum height of the triangle
Lesson Performance TaskWhen planning an airplane route the trip planner must be careful to consider the range the aircraft can travel and the availability of airports to stop and refuel
A large commercial jet airplane burns approximately 5 gallons of fuel per mile flown plus about 8500 gallons of fuel per trip to reach cruising altitude With a useable fuel capacity of 50000 gallons (there is additional fuel reserved for emergencies) describe the acceptable distance for which an airline could establish a non-stop flight
For flights originating from Chicago determine which cities could be safely reached by a non-stop flight
City Distance from Chicago (miles)
Bangalore India 8530
Jakarta Indonesia 9810
Johannesburg South Africa 8680
Moscow Russia 4970
Paris France 4130
Perth Australia 10970
Tokyo Japan 6300
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eva O
lesiaShutterstock
(2x - 3) in
4 in
Module 2 80 Lesson 4
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Name Class Date
Resource Locker
Explore Truth Tables and Compound StatementsA compound statement is formed by combining two or more simple statements A compound statement can be true or false A compound statement involving AND is true when both simple statements are true A compound statement involving OR is true when either one simple statement or both are true
A Complete the truth table
P QP
True or FalseQ
True or FalseP AND Q
True or False
A dog is a mammal Red is a color
A dog is a mammal Red is not a color
A dog is a fish Red is a color
A dog is a fish Red is not a color
B P AND Q is true when
C Complete the truth table
P QP
True or FalseQ
True or FalseP OR Q
True or False
1 is an odd number 2 is an even number
1 is an odd number 2 is an odd number
1 is an even number 2 is an even number
1 is an even number 2 is an odd number
D P OR Q is true when
Reflect
1 Give two simple statements P and Q for which P AND Q is false and P OR Q is true
Module 2 81 Lesson 5
25 Creating and Solving Compound Inequalities
Essential Question How can you solve a compound inequality and graph the solution set
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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Explain 1 Solving Compound Inequalities Involving ANDCombining two or more simple inequalities forms a compound inequality The graph of a compound inequality involving AND is the intersection or the overlapping region of the simple inequality graphs
Compound Inequalities AND
Words Algebra Graph
All real numbers greater than 2AND less than 6
x gt 2 AND x lt 62 lt x lt 6
All real numbers greater than or equal to 2 AND less than or equal to 6
x ge 2 AND x le 62 le x le 6
Example 1 Solve each compound inequality and graph the solutions
A 4 le x + 2 le 8
4 le x + 2 AND x + 2 le 8 Write the compound inequality using AND
4 - 2 le x + 2 - 2 x + 2 - 2 le 8 - 2 Subtract 2 from both sides of each simple inequality
2 le x x le 6 Simplify
Graph 2 le x
Graph x le 6
Graph the intersection by finding where the two graphs overlap
B -5 le 2x + 3 lt 9
-5 - le 2x + 3 - lt 9 - Subtract from each part of the inequality
le 2x lt Simplify
-8 _ le 2x _ lt 6 _ Divide each part of the inequality by
le x lt Simplify
Graph -4 le x
Graph x lt 3
Graph the intersection by finding where the two graphs overlap -1 0 1 2 3 4 5-5-4 -3 -2
0 2 4 6 8 10 12-8-6-4 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 82 Lesson 5
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Reflect
2 Discussion Explain why 2 le x le 6 can be considered the short method for writing the AND compound inequality x ge 2 AND x le 6
YourTurn
Solve each compound inequality and graph the solutions
3 -2 lt x - 3 lt 5
4 -10 lt 3x + 2 le 8
Explain 2 Solving Compound Inequalities Involving ORThe graph of a compound inequality involving OR is the union or the combined region of the simple inequality graphs
Compound Inequalities OR
Words Algebra Graph
All real numbers less than 2OR greater than 6
x lt 2 OR x gt 6
All real numbers less than or equal to 2OR greater than or equal to 6
x le 2 OR x ge 6
-1 0 1 2 3 4 5-5-4 -3 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 83 Lesson 5
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oug
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pany
Example 2 Solve each compound inequality and graph the solutions
A -4 + x gt 1 OR -4 + x lt -3
-4 + x gt 1 OR -4 + x lt -3 Write the compound inequality using OR
-4 + 4 + x gt 1 + 4 -4 + 4 + x lt -3 + 4 Add 4 to both sides of each simple inequality
x gt 5 x lt 1 Simplify
Graph x gt 5
Graph x lt 1
Graph the union by combining the graphs
B 2x le 6 OR 3x gt 12
2x le 6 OR 3x gt 12 Write the compound inequality using OR
2x _ le 6 _ OR 3x _ gt 12 _ Divide the first simple inequality by
x le OR x gt
Graph x le 3
Graph x gt 4
Graph the union by combining the graphs
Reflect
5 Critical Thinking What kind of compound inequality has no solution
Divide the second simple inequality by
Simplify
0 1 2 3 4 5 6-4 -3 -2 -1
-0 1 2 3 4 5 6-4 -3 -2 -1
Module 2 84 Lesson 5
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oug
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Your Turn
Solve each compound inequality and graph the solutions
6 x - 5 ge -2 OR x -5 le -6
7 4x -1 lt 15 OR 8x ge 48
Explain 3 Creating Compound Inequalities From GraphsGiven a number line graph with a solution set graphed you can create a compound inequality to fit the graph
Example 3 Write the compound inequality shown by each graph
A
The shaded portion of the graph is not between two values so the compound inequality involves OR
On the left the graph shows an arrow pointing left from -1 and a solid circle so use le
The inequality is x le -1
On the right the graph shows an arrow pointing right from 7 and a solid circle so use ge
The inequality is x ge 7
The compound inequality is x le -1 OR x ge 7
B
The graph is shaded between the values and so the compound inequality involves AND
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The compound inequality is
-1 0 1 2 3 4 5-5-4 -3 -2
4 5 6 7 8 9 100 1 2 3
2 3 4 5 6 7 8-2 -1 0 1
10 2 3 4 5 6 7 8 9-1
Module 2 85 Lesson 5
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oug
hton Mifflin H
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Reflect
8 What is a short method to write the compound inequality x ge 0 AND x lt 6
Your Turn
Write the compound inequality shown by each graph
9
10
Explain 4 Expressing Acceptable Levels with Compound Inequalities
You can express quality-controls levels in real-world problems using compound inequalities
Example 4 Write a compound inequality to represent the indicated quality-control level and graph the solutions
A The recommended pH level for swimming pool water is between 72 and 76 inclusive
Let p be the pH level of swimming pool water
72 is less than or equal to pH level is less than or equal to 76
72 le p le 76
The compound inequality is 72 le p le 76
Graph the solutions
0-10 -8-9 -7-6 -5-4 -3 -2 -1
71 72 73 74 75 76 77 78 79 8070
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 86 Lesson 5
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oug
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B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
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oug
hton Mifflin H
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bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
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oug
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Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
arcourt Publishin
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age C
redits copy
Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
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oug
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Mif
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bik
erid
erlo
nd
onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
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oug
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The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
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Elaborate
11 When given an algebraic expression involving subtraction why is it best to rewrite the expression using addition before identifying the terms
12 How do you interpret algebraic expressions in terms of their context
13 How do you simplify algebraic expressions
14 Essential Question Check In How do you write algebraic expressions to model quantities
bull Online Homeworkbull Hints and Helpbull Extra Practice
Evaluate Homework and PracticeIdentify the terms and the coefficients of the expression
1 -20 + 5p - 7z 2 8x - 20y - 10
Identify the factors of the terms of the expression
3 5 + 6a + 11b 4 13m - 2n
5 Erin is buying produce at a store She buys c cucumbers at $099 each and a apples at $079 each What does the expression 099c + 079a represent
6 The number of bees that visit a plant is 500 times the number of years the plant is alive where t represents the number of years the plant is alive What does the expression 500t represent
Evaluate Homework and Practice
Module 2 49 Lesson 1
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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oug
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Leonard
LenzC
orbis
7 Lorenzo buys 3 shirts at s dollars apiece and 2 pairs of pants at p dollars a pair What does the expression 3s + 2p represent
8 If a car travels at a speed of 25 mih for t hours then travels 45 mih for m hours what does the expression 25t + 45m represent
9 The price of a sandwich is $150 more than the price of a smoothie which is d dollars What does the expression d + 15 represent
10 A bicyclist travels 1 mile in 5 minutes If m represents minutes what does the expression m __ 5 represent
11 What are the factors of the expression (y - 2)(x + 3)
12 Explain the Error A student wrote that there are two terms in the expression 3p - (7 - 4q) Explain the studentrsquos error
13 Yolanda is buying supplies for school She buys n packages of pencils at $140 per package and m pads of paper at $120 each What does each term in the expression 14n + 12m represent What does the entire expression represent
14 Chris buys p pairs of pants and 4 more shirts than pairs of pants Shirts cost $18 each and pair of pants cost $25 each What does each term in the expression 25p + 18(p + 4) represent What does the entire expression represent
Module 2 50 Lesson 1
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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mag
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copyJe
ssie
W
alke
rLi
ved
In Im
ages
Cor
bis
Suppose a and b give the populations of two states where a gt b Compare the expressions and tell which of the given pair is greater or if the expressions are equal
15 b _ a + b
and 05
16 a + 13c and b + 13c where c is the population of a third state
17 a - b _ 2 and a - b _ 2
18 a + b and 2b
19 5(a + b) and (a + b)5
Write an algebraic expression to model the given context Give your answer in simplest form
20 the price s of a pair of shoes plus 5 sales tax 21 the original price p of an item less a discount of 20
22 the price h of a recently bought house plus 10 property tax
23 the principal amount P originally deposited in a bank account plus 03 interest
Module 2 51 Lesson 1
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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arcourt Publishin
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pany
24 Match each statement with the algebraic expression that models it
A the price of a winter coat and a 20 discount x + 002x = 102x
B the base salary of an employee and a 2 salary increase x - 020x = 080x
C the cost of groceries and a 2 discount with coupons x + 020x = 120x
D the number of students attending school last year and a 20 increase from last year x - 002x = 098x
HOT Focus on Higher Order Thinking
25 Critique Reasoning A student is given the rectangle and the square shown The student states that the two figures have the same perimeter Is the student correct Explain your reasoning
26 Multi-Step Yon buys tickets to a concert for himself and a friend There is a tax of 6 on the price of the tickets and an additional booking fee of $20 for the transaction Write an algebraic expression to represent the price per person Simplify the expression if possible
x + 2
x + 2x
x + 4
Module 2 52 Lesson 1
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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27 Persevere in Problem Solving Jerry is planting white daisies and red tulips in his garden and he wants to choose a pattern in which the tulips surround the daisies He uses tiles to generate patterns starting with two rows of three daisies He surrounds these daisies with a border of tulips The design continues as shown
a Jerry writes the expression 8(b - 1) + 10 for the number of tulips in each border wherein b is the border number and b ge 1 Explain why Jerryrsquos expression is correct
b Elaine wants to start with two rows of four daisies Her reasoning is that Jerry started with two rows of three daisies and his expression was 8(b - 1) + 10 so if she starts with two rows of four daisies her expression will be 10(b - 1) + 10 Is Elainersquos statement correct Explain
Border 1 Border 2 Border 3
Module 2 53 Lesson 1
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
Lesson Performance Task
Becky and Michele are both shopping for a new car at two different dealerships Dealership A is offering $500 cash back on any purchase while Dealership B is offering $1000 cash back The tax rate is 5 at Dealership A but 8 at Dealership B Becky wants to buy a car that is $15000 and Michele is planning to buy a car that costs $20000 Use algebraic expressions to help you answer the following questions
a At which dealership will Becky get the better deal How much does she save
b At which dealership will Michele get the better deal How much does she save
c What generalization can you make that would help any shopper know which dealership has the better deal [Hint At what price point would the two deals be equal]
copy H
oug
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redits copy
Tom G
rillC
orbis
Module 2 54 Lesson 1
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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Mif
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Com
pan
y
Name Class Date
Resource Locker
Explore Creating Equations from Verbal Descriptions
You can use what you know about writing algebraic expressions to write an equation that represents a real-world situation
Suppose Cory and his friend Walter go to a movie Each of their tickets costs the same amount and they share a frozen yogurt that costs $550 The total amount they spend is $1990 How can you write an equation that describes the situation
A Identify the important information
The word tells you that the relationship describes an equation
The word total tells you that the operation involved in the relationship is
What numerical information do you have
What is the unknown quantity
B Write a verbal description
Choose a name for the variable In this case use c for
The verbal description is Twice the cost of plus the cost
of equals
C To write an equation write a numerical or expression for each quantity
and insert an equal sign in the appropriate place An equation is
Reflect
1 How can you use a verbal model to write an equation for the situation described
Module 2 55 Lesson 2
22 Creating and Solving EquationsEssential Question How do you use an equation to model and solve a real-world problem
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igital
Vision
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ages
2 Could you write a different equation to describe the situation Explain your reasoning
Explain 1 Creating and Solving Equations Involving the Distributive Property
When you create an equation to model a real-world problem your equation may involve the Distributive Property When you solve a real-world problem you should always check that your answer makes sense
Example 1 Write and solve an equation to solve each problem
A Aaron and Alice are bowling Alicersquos score is twice the difference of Aaronrsquos score and 5 The sum of their scores is 320 Find each studentrsquos bowling score
Write a verbal description of the basic situation
The sum of Aaronrsquos score and Alicersquos score is 320
Choose a variable for the unknown quantity and write an equation to model the detailed situation
Let a represent Aaronrsquos score Then 2 (a - 5) represents Alicersquos score
a + 2 (a - 5) = 320
Solve the equation for a
a + 2 (a - 5) = 320
a + 2a - 10 = 320 Distributive Property
3a - 10 = 320
3a - 10 + 10 = 320 + 10 Addition Property of Equality
3a = 330
3a _ 3 = 330 _ 3 Division Property of Equality
a = 110
So Aaronrsquos score is 110 and Alicersquos score is 2 (a - 5) = 2 (110 - 5) = 2 (105) = 210
Check that the answer makes sense
110 + 210 = 320 so the answer makes sense
B Mari Carlos and Amanda collect stamps Carlos has five more stamps than Mari and Amanda has three times as many stamps as Carlos Altogether they have 100 stamps Find the number of stamps each person has
Write a verbal description of the basic situation
Module 2 56 Lesson 2
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pan
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Choose a variable for the unknown quantity and write an equation to model the detailed situation
Let s represent the number of stamps Mari has Then Carlos has stamps
and Amanda has stamps
s + + 3 ( ) =
Solve the equation for s
s + + 3 ( ) =
s + s + 5 + 3s + = Distributive Property
+ = Combine like terms
s = Subtraction Property of Equality
s = Division Property of Equality
So Mari has stamps Carlos has stamps and Amanda
has stamps
Check that the answer makes sense
+ + = the answer makes sense
=
Reflect
3 Would a fractional answer make sense in this situation
4 Discussion What might it mean if a check revealed that the answer to a real-world problem did not make sense
Module 2 57 Lesson 2
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pany
Your Turn
Write and solve an equation to solve the problem
5 A rectangular garden is fenced on all sides with 256 feet of fencing The garden is 8 feet longer than it is wide Find the length and width of the garden
Explain 2 Creating and Solving Equations with Variables on Both Sides
In some equations variables appear on both sides You can use the properties of equality to collect the variable terms so that they all appear on one side of the equation
Example 2 Write and solve an equation to solve each problem
A Janine has job offers at two companies One company offers a starting salary of $28000 with a raise of $3000 each year The other company offers a starting salary of $36000 with a raise of $2000 each year In how many years would Janinersquos salary be the same with both companies What will the salary be
Write a verbal description of the basic situation
Let n represent the number of years it takes for the salaries to be equal
Base Salary A plus $3000 per year raise = Base Salary B + $2000 per year raise
28000 + 3000n = 36000 + 2000n
28000 + 3000n - 2000n = 36000 + 2000n - 2000n Subtraction Property of Equality
28000 + 1000n = 36000 Combine like terms
28000 + 1000n - 28000 = 36000 - 28000 Subtraction Property of Equality
1000n = 8000 1000n _ 1000 = 8000 _ 1000 Division Property of Equality
n = 8
28000 + 3000 (8) = 36000 + 2000 (8)
52000 = 52000
In 8 years the salaries offered by both companies will be $52000
(w + 8) feet
w feet
Module 2 58 Lesson 2
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oug
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Har
cour
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pan
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B One moving company charges $800 plus $16 per hour Another moving company charges $720 plus $21 per hour At what number of hours will the charge by both companies be the same What is the charge
Write a verbal description of the basic situation Let t represent the number of hours that the move takes
Moving Charge A plus $16 per hour = Moving Charge B plus $21 per hour
800 + t = 720 + t
800 + t - t = 720 + t - t Subtraction Property of Equality
800 = 720 + t
800 - 720 = 720 + t - 720 Subtraction Property of Equality
= t
_ = t _
Division Property of Equality
t =
The charges are the same for a job that takes hours
Substitute the value 16 in the original equation
800 + 16t = 720 + 21t
800 + 16 ( ) = 720 + 21 ( ) 800 + = 720 +
=
After hours the moving charge for both companies will be
Reflect
6 Suppose you collected the variable terms on the other side of the equal sign to solve the equation Would that affect the solution
Module 2 59 Lesson 2
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oug
hton Mifflin H
arcourt Publishin
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pany
Your Turn
Write and solve an equation to solve each problem7 Claire bought just enough fencing to enclose either a
rectangular garden or a triangular garden as shown The two gardens have the same perimeter How many feet of fencing did she buy
8 A veterinarian is changing the diets of two animals Simba and Cuddles Simba currently consumes 1200 Calories per day That number will increase by 100 Calories each day Cuddles currently consumes 3230 Calories a day That number will decrease by 190 Calories each day The patterns will continue until both animals are consuming the same number of Calories each day In how many days will that be How many Calories will each animal be consuming each day then
Explain 3 Constructing Equations from an Organized TableYou can use a table to organize information and see relationships
Example 3 Construct and solve an equation to solve the problem
Kim works 4 hours more each day than Jill does and Jack works 2 hours less each day than Jill does Over 2 days the number of hours Kim works is equal to the difference of 4 times the number of hours Jack works and the number of hours Jill works How many hours does each person work each day
Analyze Information
Identify the important information
bull Kim works hours more per day than Jill does
bull Jack works hours less per day than Jill does
Formulate a Plan
Make a table using the information given Let x be the number of hours Jill works in one day
Hours Worked Per Day Hours Worked Over 2 Days
Kim
Jill
Jack
Over 2 days the number of hours Kim works is equal to the difference of 4 times the number of hours Jack works and the number of hours Jill works
(3x - 3)(x - 3)
(2x - 1) (2x - 1)
2x
Module 2 60 Lesson 2
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Solve
2 (x + 4) = 4 2 (x - 2) - 2x
2 (x + 4) = (x - 2) - 2x Simplify
2x + = 8x - - 2x Distributive Property
2x + 8 = x - 16
2x + 8 + = 6x - 16 + Addition Property of Equality
2x + = 6x
2x + 24 - x = 6x - x Subtraction Property of Equality
24 = x
24 _ = x _ Division Property of Equality
= x
Jill works hours per day Kim works hours per day and Jack works
hours per day
Justify and Evaluate
Substitute x = 6 into the original equation
2 (6 + 4) = 4 2 (6 - 2) - 2x
2 ( ) = 8 ( ) - 2 ( ) =
Your Turn
Write and solve an equation to solve the problem
9 Lisa is 10 centimeters taller than her friend Ian Ian is 14 centimeters taller than Jim Every month their heights increase by 2 centimeters In 7 months the sum of Ianrsquos and Jimrsquos heights will be 170 centimeters more than Lisarsquos height How tall is Ian now
Height now Height after 7 months
Module 2 61 Lesson 2
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oug
hton Mifflin H
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pany
Elaborate
10 How can you use properties to solve equations with variables on both sides
11 How is a table helpful when constructing equations
12 When solving a real-world problem to find a personrsquos age would a negative solution make sense Explain
13 Essential Question Check-In How do you write an equation to represent a real-world situation
bull Online Homeworkbull Hints and Helpbull Extra Practice
Write an equation for each description
1 The sum of 14 and a number is equal to 17 2 A number increased by 10 is 114
3 The difference between a number and 12 is 20 4 Ten times the sum of half a number and 6 is 8
5 Two-thirds a number plus 4 is 7 6 Tanmayi wants to raise $175 for a school fundraiser She has raised $120 so far How much more does she need to reach her goal
7 Hector is visiting a cousin who lives 350 miles away He has driven 90 miles How many more miles does he need to drive to reach his cousinrsquos home
8 The length of a rectangle is twice its width The perimeter of the rectangle is 126 feet
Evaluate Homework and Practice
Module 2 62 Lesson 2
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oug
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cour
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pan
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(t)copy
Pete
r K
imS
hutt
erst
ock
Write and solve an equation for each situation
9 In one baseball season Peter hit twice the difference of the number of home runs Alice hit and 6 Altogether they hit 18 home runs How many home runs did each player hit that season
10 The perimeter of a parallelogram is 72 meters The width of the parallelogram is 4 meters less than its length Find the length and the width of the parallelogram
11 One month Ruby worked 6 hours more than Isaac and Svetlana worked 4 times as many hours as Ruby Together they worked 126 hours Find the number of hours each person worked
12 In one day Annie traveled 5 times the sum of the number of hours Brian traveled and 2 Together they traveled 20 hours Find the number of hours each person traveled
13 Xian and his cousin Kai both collect stamps Xian has 56 stamps and Kai has 80 stamps The boys recently joined different stamp-collecting clubs Xianrsquos club will send him 12 new stamps per month Kairsquos club will send him 8 new stamps per month After how many months will Xian and Kai have the same number of stamps How many stamps will each have
14 Kenya plans to make a down payment plus monthly payments in order to buy a motorcycle At one dealer she would pay $2500 down and $150 each month At another dealer she would pay $3000 down and $125 each month After how many months would the total amount paid be the same for both dealers What would that amount be
ℓ meters
(ℓ - 4) meters
Module 2 63 Lesson 2
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copy H
oug
hton Mifflin H
arcourt Publishin
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pany
15 Community Gym charges a $50 membership fee and a $55 monthly fee Workout Gym charges a $200 membership fee and a $45 monthly fee After how many months will the total amount of money paid to both gyms be the same What will the amount be
16 Tina is saving to buy a notebook computer She has two options The first option is to put $200 away initially and save $10 every month The second option is to put $100 away initially and save $30 every month After how many months would Tina save the same amount using either option How much would she save with either option
Use the table to answer each question
Starting Salary Yearly Salary Increase
Company A $24000 $3000
Company B $30000 $2400
Company C $36000 $2000
17 After how many years are the salaries offered by Company A and Company B the same
18 After how many years are the salaries offered by Company B and Company C the same
19 Paul started work at Company B ten years ago at the salary shown in the table At the same time Sharla started at Company C at the salary shown in the table Who earned more during the last year How much more
20 Georgersquos page contains twice as many typed words as Billrsquos page and Billrsquos page contains 50 fewer words than Charliersquos page If each person can type 60 words per minute after one minute the difference between twice the number of words on Billrsquos page and the number of words on Charliersquos page is 210 How many words did Billrsquos page contain initially Use a table to organize the information
Initial number of words
Total number of words after one minute
Module 2 64 Lesson 2
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oug
hton
Mif
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Har
cour
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lishi
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Com
pan
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21 Geometry Sammie bought just enough fencing to border either a rectangular plot or a square plot as shown The perimeters of the plots are the same How many meters of fencing did she buy
HOT Focus on Higher Order Thinking
22 Justify Reasoning Suppose you want to solve the equation 2a + b = 2a where a and b are nonzero real numbers Describe the solution to this equation Justify your description
23 Multi-step A patio in the shape of a rectangle is fenced on all sides with 134 feet of fencing The patio is 5 feet less wide than it is long
a What information can be used to solve the problem How can you find the information
b Describe how to find the area of the patio What is the area of the patio
24 Explain the Error Kevin and Brittany write an equation to represent the following relationship and both students solve their equation Who found the correct equation and solution Why is the other person incorrect
5 times the difference of a number and 20 is the same as half the sum of 4 more than 4 times a number
Kevin Brittany
5 (x - 20) = 1 _ 2 (4x + 4) 5 (20 + x) = 1 _ 2 (4x + 4)
5x - 100 = 2x + 2 100 - 5x = 2x + 2
3x - 100 = 2 100 - 7x = 2
3x = 102 -7x = -98
x = 34 x = 14
(3x + 2) meters
(x + 2) meters
(x + 2) meters
(x - 1) meters
ℓ feet
(ℓ - 5) feet
Module 2 65 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
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pany
25 What If Alexa and Zack are solving the following problem
The number of miles on Car A is 50 miles more than the number of miles on Car B and the number of miles on Car B is 30 miles more than the number of miles on Car C All the cars travel 50 miles in 1 hour After 1 hour twice the number of miles on Car A is 70 miles less than 3 times the number of miles on Car C How many miles were there on Car B initially
Alexa assumes there are m miles on Car B Zack assumes there are m miles on Car C Will Zackrsquos answer be the same as Alexarsquos answer Explain
Lesson Performance Task
Stacy Oliver and Jivesh each plan to put a certain amount of money into their savings accounts that earn simple interest of 6 per year Stacy puts $550 more than Jivesh and Oliver puts in 2 times as much as Jivesh After a year the amount in Stacyrsquos account is 2 times the sum of $212 and the amount in Oliverrsquos account How much does each person initially put into his or her account Who had the most money in his or her account after a year Who had the least Explain
Zackrsquos Table Initial Miles
Miles after One Hour
Alexarsquos Table Initial Miles
Miles after One Hour
Amount in Account Initially Amount in Account after One Year
Module 2 66 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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cour
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pan
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Name Class Date
Resource Locker
Explore Rearranging Mathematical FormulasLiteral Equations are equations that contain two or more variables There are many literal equations in the form of math science and engineering formulas These formulas may seem like they can only be solved for the variable that is isolated on one side of the formula By using inverse operations and the properties of equality a formula can be rearranged so any variable in the formula can be isolated It is no different than how equations are solved by using inverse operations and the properties of equality
How can you solve the equation 42 = 6x
A42 _ = 6x _ What is the reason for dividing
Why divide by
= x By rearranging the equation x was isolated and the solution was found
The mathematical formula for the volume of a rectangular prism B = Vh or V = ℓwh is a literal equation V represents volume ℓ represents length w represents width and h represents height Using inverse operations the formula can be rearranged to solve for any one of the variables that might be unknown Like solving for x a formula can be rearranged to isolate a variable
B In the formula V = ℓwh the variable h needs to be isolated
The operation of is used in the formula The inverse
operation should be used
to isolate
C V _____ = ℓwh _____
V _ =
The formula rearranged in this way can easily produce the height of the rectangular prism when the volume length and width are known
Reflect
1 Using the formula for a rectangular prism rewrite the formula to solve for ℓ
ℓw
h
Module 2 67 Lesson 3
23 Solving for a VariableEssential Question How do you rewrite formulas and literal equations
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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Photo
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otosCorb
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Explain 1 Rearranging Scientific FormulasUse inverse operations to isolate the unknown variable in a scientific formula
The formula for density is D = m __ V Lead has a very high density of 11340 kg m 3 Plastic foam has a very low density of 75 kg m 3 The formula for density can be rearranged to solve for V volume or m mass
Example 1
A A sinker on a fishing line is made of lead and has a volume of 0000015 m 3 What is the mass of the sinker
The density formula can be rearranged to isolate m the mass The values for volume and density can then be substituted into the formula to find the mass
D = m _ V
DV = ( m _ V ) V DV = m
(11340 kg m 3 ) (0000015 m 3 ) = m
017 kg asymp m
B The design for a life preserver requires 03 kilogram of plastic foam to provide proper buoyancy What is the volume of the plastic foam required
Rearrange the density formula to isolate V
D = m _ V
(D) V = m _ V
DV =
DV _ = m _
V =
Now substitute the given values
V = _
V = m 3
Your Turn
2 For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Determine the altitude in feet when t is -275 ∘F and g is 60 ∘F
Module 2 68 Lesson 3
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Explain 2 Rearranging Literal EquationsUsing inverse operations to rearrange literal equations can be applied to any formula The interest formula I = prt is another example of a literal equation In the formula I represents interest p the principal or the initial amount to which interest will be applied r the rate at which interest will be paid and t is the time in years
Example 2
A Find the number of years used in the calculation of a $1000 loan at an interest rate of 5 with interest totaling $600
Solve the formula for t
I = prt
I _ pr = prt
_ pr
I _ pr = t
Substitute the given values Since the interest rate is 5 r = 005$600 __
$1000 middot 005 = t
12 = t
So the length of time for the loan is 12 years
B Determine the interest rate for a $2000 loan that will be paid off in 4 years with interest totaling $640 In order to find the interest rate solve the formula for r
I = prt
I _ = prt _
_ = r
Now substitute the values and simplify
__
( ) ( ) = r
008 = r
So the interest rate is per year
Your Turn
3 The formula y = mx + b is the slope-intercept form of the equation of a line Solve the equation for m
Module 2 69 Lesson 3
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
copy H
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bull Online Homeworkbull Hints and Helpbull Extra Practice
Solve for the indicated variable in each mathematical formula
1 C = 2πr for r 2 A = 1 __ 2 bh for b 3 y = mx + b for x
4 A = 1 __ 2 (a + b)h for h 5 V = πr2h for h 6 SA = 2πr2 + 2πrh for h
Solve for the indicated variable in each scientific formula
7 d = rt for t 8 PV = nRT for T
9 A = FV - OV _______ T for OV 10 C = Wtc _ 1000 for W
Evaluate Homework and Practice
Elaborate
4 Discussion What could be a reason for isolating a variable in a literal equation
5 Describe a situation in which a formula could be used more easily if it were rearranged Include the formula in your description
6 Essential Question Check-In How do you isolate a variable
Module 2 70 Lesson 3
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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Mif
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cour
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pan
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mag
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copyO
cean
C
orb
is
Solve for the indicated variable in each literal equation
11 2p + 5r = q for p 12 -10 = xy + z for x 13 a __ b = c for b
14 h - 4 _ j = k for j 15 x __ 5 - g = a for x 16 5p + 9c = p for c
17 2 __ 5 (z + 1) = y for z 18 g (h + 2 __ 3 ) = 1 for h 19 a(n - 3) + 8 = bn for n
20 Which is a possible way to rewrite the equation y = 3x + 3b to solve for b
A b = y - 3x
_ 3 C b = y - 3
_____ 3x
B b = 3(y - 3x) D b = x(y - 3)
21 Sports To find a baseball pitcherrsquos earned run average (ERA) you can use the formula Ei = 9r in which E represents ERA i represents the number of innings pitched and r represents the number of earned runs allowed Solve the equation for E What is a pitcherrsquos ERA if he allows 5 earned runs in 18 innings pitched
22 Meteorology For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Solve the equation for a If the atmospheric temperature is -655 ∘F and the ground temperature is 57 ∘F what is the altitude
Module 2 71 Lesson 3
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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arcourt Publishin
g Com
pany bull Im
age C
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Rand
y D
uch
aineA
lamy
HOT Focus on Higher Order Thinking
23 Explain the Error A student was asked to use the formula for the perimeter of a rectangle P = 2ℓ + 2w to solve for ℓ The student came up with an answer P - 2w = 2ℓ What error did the student make Explain Then solve for ℓ
24 Multi-Step The formula c = 5p + 215 relates c the total cost in dollars of hosting a birthday party at a skating rink to p the number of people attending If Alliersquos parents are willing to spend $300 for a party how many people can attend
25 Multi-Step The formula for the area of a triangle is A = 1 __ 2 bh in which b represents the length of thebase and h represents the height If a triangle has an area of 192 mm2 and the height is 12 mm what is the measure of the base
Lesson Performance TaskThe following table shows the average low temperatures in Fahrenheit for the city of Boston for several months during the year The formula F = 9 __ 5 C + 32 allows you to determine the temperature in Fahrenheit when given the temperature in Celsius
MonthTemperature in
FahrenheitTemperature in
Celsius
January 22deg
April 41deg
July 65deg
October 47deg
December 28deg
a Use the information given to determine the average low temperatures in Celsius
b Would it ever be possible for the temperature in Celsius to have a greater value than the temperature in Fahrenheit Explain why or why not
Module 2 72 Lesson 3
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
Name Class Date
Resource Locker
copy H
oug
hton
Mif
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Har
cour
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Com
pan
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mag
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edit
s copy
Patr
ick
Lan
eSo
mos
Imag
esC
orb
is
Explore Creating Inequalities from Verbal DescriptionsAn inequality is a statement that compares two expressions that are not strictly equal by using one of the following inequality signs
Symbol Meaning
lt is less than
le is less than or equal to
gt is greater than
ge is greater than or equal to
ne is not equal to
You have probably seen a sign at an amusement park saying something like ldquoYou must be at least 48 inches tall to ride this riderdquo This statement could be written as h ge 48 in where h represents the height of a person allowed to ride
Nora is planning a birthday party for her little sister Colleen Norarsquos budget will allow her to spend no more than $50 for party supplies Eight children including Colleen will attend the party and Nora wants to determine how much she could spend on party favors for each child She will also purchase a cake for $10 Write an inequality that represents the situation and find possible solutions
A First let c represent the cost of a party favor for each child Write an expression for the total cost of the party as a function of c
c +
B Which inequality symbol should be used to represent the phrase ldquono more thanrdquo
C Write the inequality that represents Norarsquos budget goal
8c + 10 le
D Suppose Nora finds party favors that cost $4 each Use a value of 4 for c and check to see if this inequality is true
8 middot 4 + 10 le 50
le 50
Module 2 73 Lesson 4
24 Creating and Solving Inequalities
Essential Question How do you write and solve an inequality that represents a real-world situation
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany
Is the inequality true
Could Nora buy $6 party favors for all of her guests without going over budget
Reflect
1 Why does an inequality represent Norarsquos budget calculation better than an equation
2 The solution set of an inequality consists of all values that make the statement true Describe the whole dollar amounts that are in the solution set for this situation
Explain 1 Creating and Solving Inequalities Involving the Distributive Property
You may need to use the Distributive Property before you can solve an inequality
Distributive Property If a b and c are real numbers then a(b + c) = ab + ac
The inequality sign must be reversed when multiplying or dividing both sides of an inequality by a negative number
Example 1
A Trina is buying 12 shirts for the drama club She will choose a style for the blank shirts and then pay an additional charge of $275 for each shirt to have the club logo If Trina cannot spend more than $99 how much can she spend on each blank shirt Write and solve an inequality to find the possible cost of each blank shirt
Let s represent the cost of each blank shirt
Write an inequality to represent the situation 12(s + 275) le 99
Use the Distributive Property 12s + 33 le 99
Subtraction Property of Inequality 12s + 33 - 33 le 99 - 33
Simplify 12s le 66
Division Property of Inequality 12s ___ 12 le 66 __ 12
Simplify s le 55
Module 2 74 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
copy H
oug
hton
Mif
flin
Har
cour
t Pub
lishi
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Com
pan
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Check your answer
Since s le 55 check a smaller number 12(5 + 275) le 99
Trina can order blank shirts that cost $550 or less 93 le 99 true
B Sergio needs to buy gifts for 8 friends He wants to give the same gift to all his friends and he plans to have the gifts wrapped for an additional charge of $150 each If Sergio spends at least $70 he will receive free shipping on his order Write and solve an inequality to determine how much Sergio needs to spend on each gift in order to receive free shipping
Let g be the cost of one gift
Write an inequality to represent the situation ( g + ) ge 70
Use the Distributive Property g + ge 70
Subtraction Property of Inequality g + 12 - ge 70 -
Simplify 8g ge
Division Property of Inequality 8g _
ge 58 _
Simplify g ge
Check your answer
Since g ge 725 check a larger number 8(8 + 150) ge 70
Sergio must spend at least on each gift ge 70
Reflect
3 Discussion Why is the first step in solving the inequality to use the Distributive Property instead of working inside the parentheses
Your Turn
4 Zachary is planning to send a video game to each of his two brothers If he buys the same game for both brothers and pays $475 to ship each game how much can he spend on each game without spending more than $100 Write and solve an inequality for this situation
Solve each inequality
5 4 _ 3 (6x + 9) lt 4 6 -2 ( 1 _ 4 x + 2 ) ge 5
Module 2 75 Lesson 4
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Explain 2 Creating and Solving Inequalities with Variables on Both Sides
Some inequalities have variable terms on both sides of the inequality symbol You can solve these inequalities the same way you solved equations with variables on both sides Use the properties of inequality to collect all the variable terms on one side and all the constant terms on the other side
Example 2
A The Daily Info charges a fee of $650 plus $80 per week to run an ad The Peoplersquos Paper charges $145 per week For how many weeks must an ad run for the total cost at the Daily Info to be less expensive than the cost at the Peoplersquos Paper Let w be the number of weeks the ad runs in the paper
Write an inequality to represent the situation 650 + 80w lt 145w
Subtraction Property of Inequality 650 + 80w - 80w lt 145w - 80w
Simplify 650 lt 65w
Division Property of Inequality 650 _ 65 lt 65w _ 65
Simplify 10 lt w
The total cost at the Daily Info is less than the cost at the Peoplersquos Paper if the ad runs for more than 10 weeks
B The Home Cleaning Company charges $312 to power-wash the siding of a house plus $12 for each window Power Clean charges $36 per window and the price includes power-washing the siding How many windows must a house have to make the total cost from The Home Cleaning Company less expensive than Power Clean Let w be the number of windows
Write an inequality to represent the situation +12w lt 36w
Subtraction Property of Inequality 312 + 12w - lt 36w -
Simplify 312 lt
Division Property of Inequality 312 _ lt 24w _
Simplify lt w
A house must have more than 13 windows for The Home Cleaning Company to be less expensive than Power Clean
Reflect
7 How would the final inequality change if you divided by ndash24 in the next to last step
Your Turn
8 The school band will sell pizzas to raise money for new uniforms The supplier charges $100 plus $4 per pizza The band members sell the pizzas for $7 each Write and solve an inequality to find how many pizzas the band members will have to sell to make a profit
Module 2 76 Lesson 4
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Elaborate
9 Which inequality symbol would you use to represent the following words or phrases Can you come up with more examples
a at most b farther than c younger than d up to
10 Discussion How are the steps to solving an inequality similar to those for solving an equation How are they different
11 Essential Question Check-In How can you write an inequality that represents a real-world situation
Write an inequality that represents the description and then solve
1 Max has more than 5 carrots (number of carrots Max has = c)
2 Brigitte is shorter than 5 feet (Brigittersquos height = h)
3 Twice a number (x) is less than 10 4 Six more than five times a number (x) is at least twenty-one
5 Dave has $15 to spend on an $8 book and two birthday cards (c) for his friends How much can he spend on each card if he buys the same card for each friend
6 Toni can carry up to 18 lb in her backpack Her lunch weighs 1 lb her gym clothes weigh 2 lb and her books (b) weigh 3 lb each How many books can she carry in her backpack
Evaluate Homework and Practice
bull Online Homeworkbull Hints and Helpbull Extra Practice
Module 2 77 Lesson 4
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pany
Solve each inequality
7 3 (x - 2) gt -3 8 5 + 5 (x + 4) le 20 9 3 + 1 _ 2 (3 - x) lt -7
10 3 (x + 6) - 2 (x + 2) ge 10 11 5 (3 - x) -4 (2 - 3x) gt 2 12 1 _ 2 (4x - 2) - 2 _ 3 (6x + 9) le 4
13 x + 1 gt -5 (7 - 2x) 14 5 _ 3 (6x + 3) le 2x - 7
15 2x le - 2 __ 3 (4x + 4) 16 1 __ 2 (-2x - 10) gt 3 (4 - 6x)
17 -5 - 3x ge 2 (10 + 2x) + 3 18 -3 (9x + 20) ge 15x - 20
19 8 ( 1 _ 4 x - 3) + 24 lt 4 ( x + 5 ) 20 6x - 2 (x + 2) gt 2 - 3 (x + 3)
Module 2 78 Lesson 4
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21 Physics A crane cable can support a maximum load of 15000 kg If a bucket has a mass of 2000 kg and gravel has a mass of 1500 kg for every cubic meter how many cubic meters of gravel (g) can be safely lifted by the crane
22 Find the solution set of each inequality below and then determine which inequalities have the same solution set as 1 _ 3 ( -5x - 3 ) lt 14
a 1 _ 3 (5x + 3) gt -14 b 2 _ 5 (10x + 20) gt 44
c - 2 _ 5 (10x + 20) lt -44 d - 1 _ 3 (5x + 3) lt 14
e 2 _ 5 (10x - 20) gt -44 f 1 _ 3 (5x + 3) lt -14
HOT Focus on Higher Order Thinking
23 Explain the Error Sven is trying to find the maximum amount of time he can spend practicing the five scales of piano music he is supposed to be working on He has 60 minutes to practice piano and would like to spend at least 35 minutes playing songs instead of practicing scales So Sven sets up the following inequality where t is the number of minutes he spends on each scale and solves it
60 - 5t le 35-5t le -25
t ge 5
Sven has concluded that he should spend 5 minutes or more on each scale Is this correct If not what mistake did he make Then solve for the correct answer
Module 2 79 Lesson 4
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24 Critical Thinking Anika wants to determine the maximum number of tulip bulbs (t) she can purchase if each bulb costs $150 She will also need to purchase separate pots for each bulb at $125 each and a bag of potting soil for $1000 Set up an inequality to determine how many tulip bulbs Anika can purchase without spending more than $2000 and solve it Can Anika buy exactly enough bulbs and pots to spend the full $2000 Explain Can you think of a better inequality to describe the answer
25 Geometry The area of the triangle shown is no more than 10 square inches
a Write an inequality that can be used to find x
b Solve the inequality from part a c What is the maximum height of the triangle
Lesson Performance TaskWhen planning an airplane route the trip planner must be careful to consider the range the aircraft can travel and the availability of airports to stop and refuel
A large commercial jet airplane burns approximately 5 gallons of fuel per mile flown plus about 8500 gallons of fuel per trip to reach cruising altitude With a useable fuel capacity of 50000 gallons (there is additional fuel reserved for emergencies) describe the acceptable distance for which an airline could establish a non-stop flight
For flights originating from Chicago determine which cities could be safely reached by a non-stop flight
City Distance from Chicago (miles)
Bangalore India 8530
Jakarta Indonesia 9810
Johannesburg South Africa 8680
Moscow Russia 4970
Paris France 4130
Perth Australia 10970
Tokyo Japan 6300
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oug
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eva O
lesiaShutterstock
(2x - 3) in
4 in
Module 2 80 Lesson 4
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Name Class Date
Resource Locker
Explore Truth Tables and Compound StatementsA compound statement is formed by combining two or more simple statements A compound statement can be true or false A compound statement involving AND is true when both simple statements are true A compound statement involving OR is true when either one simple statement or both are true
A Complete the truth table
P QP
True or FalseQ
True or FalseP AND Q
True or False
A dog is a mammal Red is a color
A dog is a mammal Red is not a color
A dog is a fish Red is a color
A dog is a fish Red is not a color
B P AND Q is true when
C Complete the truth table
P QP
True or FalseQ
True or FalseP OR Q
True or False
1 is an odd number 2 is an even number
1 is an odd number 2 is an odd number
1 is an even number 2 is an even number
1 is an even number 2 is an odd number
D P OR Q is true when
Reflect
1 Give two simple statements P and Q for which P AND Q is false and P OR Q is true
Module 2 81 Lesson 5
25 Creating and Solving Compound Inequalities
Essential Question How can you solve a compound inequality and graph the solution set
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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Explain 1 Solving Compound Inequalities Involving ANDCombining two or more simple inequalities forms a compound inequality The graph of a compound inequality involving AND is the intersection or the overlapping region of the simple inequality graphs
Compound Inequalities AND
Words Algebra Graph
All real numbers greater than 2AND less than 6
x gt 2 AND x lt 62 lt x lt 6
All real numbers greater than or equal to 2 AND less than or equal to 6
x ge 2 AND x le 62 le x le 6
Example 1 Solve each compound inequality and graph the solutions
A 4 le x + 2 le 8
4 le x + 2 AND x + 2 le 8 Write the compound inequality using AND
4 - 2 le x + 2 - 2 x + 2 - 2 le 8 - 2 Subtract 2 from both sides of each simple inequality
2 le x x le 6 Simplify
Graph 2 le x
Graph x le 6
Graph the intersection by finding where the two graphs overlap
B -5 le 2x + 3 lt 9
-5 - le 2x + 3 - lt 9 - Subtract from each part of the inequality
le 2x lt Simplify
-8 _ le 2x _ lt 6 _ Divide each part of the inequality by
le x lt Simplify
Graph -4 le x
Graph x lt 3
Graph the intersection by finding where the two graphs overlap -1 0 1 2 3 4 5-5-4 -3 -2
0 2 4 6 8 10 12-8-6-4 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 82 Lesson 5
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Reflect
2 Discussion Explain why 2 le x le 6 can be considered the short method for writing the AND compound inequality x ge 2 AND x le 6
YourTurn
Solve each compound inequality and graph the solutions
3 -2 lt x - 3 lt 5
4 -10 lt 3x + 2 le 8
Explain 2 Solving Compound Inequalities Involving ORThe graph of a compound inequality involving OR is the union or the combined region of the simple inequality graphs
Compound Inequalities OR
Words Algebra Graph
All real numbers less than 2OR greater than 6
x lt 2 OR x gt 6
All real numbers less than or equal to 2OR greater than or equal to 6
x le 2 OR x ge 6
-1 0 1 2 3 4 5-5-4 -3 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 83 Lesson 5
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oug
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Example 2 Solve each compound inequality and graph the solutions
A -4 + x gt 1 OR -4 + x lt -3
-4 + x gt 1 OR -4 + x lt -3 Write the compound inequality using OR
-4 + 4 + x gt 1 + 4 -4 + 4 + x lt -3 + 4 Add 4 to both sides of each simple inequality
x gt 5 x lt 1 Simplify
Graph x gt 5
Graph x lt 1
Graph the union by combining the graphs
B 2x le 6 OR 3x gt 12
2x le 6 OR 3x gt 12 Write the compound inequality using OR
2x _ le 6 _ OR 3x _ gt 12 _ Divide the first simple inequality by
x le OR x gt
Graph x le 3
Graph x gt 4
Graph the union by combining the graphs
Reflect
5 Critical Thinking What kind of compound inequality has no solution
Divide the second simple inequality by
Simplify
0 1 2 3 4 5 6-4 -3 -2 -1
-0 1 2 3 4 5 6-4 -3 -2 -1
Module 2 84 Lesson 5
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oug
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Your Turn
Solve each compound inequality and graph the solutions
6 x - 5 ge -2 OR x -5 le -6
7 4x -1 lt 15 OR 8x ge 48
Explain 3 Creating Compound Inequalities From GraphsGiven a number line graph with a solution set graphed you can create a compound inequality to fit the graph
Example 3 Write the compound inequality shown by each graph
A
The shaded portion of the graph is not between two values so the compound inequality involves OR
On the left the graph shows an arrow pointing left from -1 and a solid circle so use le
The inequality is x le -1
On the right the graph shows an arrow pointing right from 7 and a solid circle so use ge
The inequality is x ge 7
The compound inequality is x le -1 OR x ge 7
B
The graph is shaded between the values and so the compound inequality involves AND
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The compound inequality is
-1 0 1 2 3 4 5-5-4 -3 -2
4 5 6 7 8 9 100 1 2 3
2 3 4 5 6 7 8-2 -1 0 1
10 2 3 4 5 6 7 8 9-1
Module 2 85 Lesson 5
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oug
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Reflect
8 What is a short method to write the compound inequality x ge 0 AND x lt 6
Your Turn
Write the compound inequality shown by each graph
9
10
Explain 4 Expressing Acceptable Levels with Compound Inequalities
You can express quality-controls levels in real-world problems using compound inequalities
Example 4 Write a compound inequality to represent the indicated quality-control level and graph the solutions
A The recommended pH level for swimming pool water is between 72 and 76 inclusive
Let p be the pH level of swimming pool water
72 is less than or equal to pH level is less than or equal to 76
72 le p le 76
The compound inequality is 72 le p le 76
Graph the solutions
0-10 -8-9 -7-6 -5-4 -3 -2 -1
71 72 73 74 75 76 77 78 79 8070
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 86 Lesson 5
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oug
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B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
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oug
hton Mifflin H
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pany
bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
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Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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age C
redits copy
Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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Mif
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cour
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Com
pan
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mag
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bik
erid
erlo
nd
onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
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oug
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The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
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Leonard
LenzC
orbis
7 Lorenzo buys 3 shirts at s dollars apiece and 2 pairs of pants at p dollars a pair What does the expression 3s + 2p represent
8 If a car travels at a speed of 25 mih for t hours then travels 45 mih for m hours what does the expression 25t + 45m represent
9 The price of a sandwich is $150 more than the price of a smoothie which is d dollars What does the expression d + 15 represent
10 A bicyclist travels 1 mile in 5 minutes If m represents minutes what does the expression m __ 5 represent
11 What are the factors of the expression (y - 2)(x + 3)
12 Explain the Error A student wrote that there are two terms in the expression 3p - (7 - 4q) Explain the studentrsquos error
13 Yolanda is buying supplies for school She buys n packages of pencils at $140 per package and m pads of paper at $120 each What does each term in the expression 14n + 12m represent What does the entire expression represent
14 Chris buys p pairs of pants and 4 more shirts than pairs of pants Shirts cost $18 each and pair of pants cost $25 each What does each term in the expression 25p + 18(p + 4) represent What does the entire expression represent
Module 2 50 Lesson 1
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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Mif
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Com
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mag
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copyJe
ssie
W
alke
rLi
ved
In Im
ages
Cor
bis
Suppose a and b give the populations of two states where a gt b Compare the expressions and tell which of the given pair is greater or if the expressions are equal
15 b _ a + b
and 05
16 a + 13c and b + 13c where c is the population of a third state
17 a - b _ 2 and a - b _ 2
18 a + b and 2b
19 5(a + b) and (a + b)5
Write an algebraic expression to model the given context Give your answer in simplest form
20 the price s of a pair of shoes plus 5 sales tax 21 the original price p of an item less a discount of 20
22 the price h of a recently bought house plus 10 property tax
23 the principal amount P originally deposited in a bank account plus 03 interest
Module 2 51 Lesson 1
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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pany
24 Match each statement with the algebraic expression that models it
A the price of a winter coat and a 20 discount x + 002x = 102x
B the base salary of an employee and a 2 salary increase x - 020x = 080x
C the cost of groceries and a 2 discount with coupons x + 020x = 120x
D the number of students attending school last year and a 20 increase from last year x - 002x = 098x
HOT Focus on Higher Order Thinking
25 Critique Reasoning A student is given the rectangle and the square shown The student states that the two figures have the same perimeter Is the student correct Explain your reasoning
26 Multi-Step Yon buys tickets to a concert for himself and a friend There is a tax of 6 on the price of the tickets and an additional booking fee of $20 for the transaction Write an algebraic expression to represent the price per person Simplify the expression if possible
x + 2
x + 2x
x + 4
Module 2 52 Lesson 1
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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27 Persevere in Problem Solving Jerry is planting white daisies and red tulips in his garden and he wants to choose a pattern in which the tulips surround the daisies He uses tiles to generate patterns starting with two rows of three daisies He surrounds these daisies with a border of tulips The design continues as shown
a Jerry writes the expression 8(b - 1) + 10 for the number of tulips in each border wherein b is the border number and b ge 1 Explain why Jerryrsquos expression is correct
b Elaine wants to start with two rows of four daisies Her reasoning is that Jerry started with two rows of three daisies and his expression was 8(b - 1) + 10 so if she starts with two rows of four daisies her expression will be 10(b - 1) + 10 Is Elainersquos statement correct Explain
Border 1 Border 2 Border 3
Module 2 53 Lesson 1
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
Lesson Performance Task
Becky and Michele are both shopping for a new car at two different dealerships Dealership A is offering $500 cash back on any purchase while Dealership B is offering $1000 cash back The tax rate is 5 at Dealership A but 8 at Dealership B Becky wants to buy a car that is $15000 and Michele is planning to buy a car that costs $20000 Use algebraic expressions to help you answer the following questions
a At which dealership will Becky get the better deal How much does she save
b At which dealership will Michele get the better deal How much does she save
c What generalization can you make that would help any shopper know which dealership has the better deal [Hint At what price point would the two deals be equal]
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oug
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redits copy
Tom G
rillC
orbis
Module 2 54 Lesson 1
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Name Class Date
Resource Locker
Explore Creating Equations from Verbal Descriptions
You can use what you know about writing algebraic expressions to write an equation that represents a real-world situation
Suppose Cory and his friend Walter go to a movie Each of their tickets costs the same amount and they share a frozen yogurt that costs $550 The total amount they spend is $1990 How can you write an equation that describes the situation
A Identify the important information
The word tells you that the relationship describes an equation
The word total tells you that the operation involved in the relationship is
What numerical information do you have
What is the unknown quantity
B Write a verbal description
Choose a name for the variable In this case use c for
The verbal description is Twice the cost of plus the cost
of equals
C To write an equation write a numerical or expression for each quantity
and insert an equal sign in the appropriate place An equation is
Reflect
1 How can you use a verbal model to write an equation for the situation described
Module 2 55 Lesson 2
22 Creating and Solving EquationsEssential Question How do you use an equation to model and solve a real-world problem
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age C
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igital
Vision
Getty Im
ages
2 Could you write a different equation to describe the situation Explain your reasoning
Explain 1 Creating and Solving Equations Involving the Distributive Property
When you create an equation to model a real-world problem your equation may involve the Distributive Property When you solve a real-world problem you should always check that your answer makes sense
Example 1 Write and solve an equation to solve each problem
A Aaron and Alice are bowling Alicersquos score is twice the difference of Aaronrsquos score and 5 The sum of their scores is 320 Find each studentrsquos bowling score
Write a verbal description of the basic situation
The sum of Aaronrsquos score and Alicersquos score is 320
Choose a variable for the unknown quantity and write an equation to model the detailed situation
Let a represent Aaronrsquos score Then 2 (a - 5) represents Alicersquos score
a + 2 (a - 5) = 320
Solve the equation for a
a + 2 (a - 5) = 320
a + 2a - 10 = 320 Distributive Property
3a - 10 = 320
3a - 10 + 10 = 320 + 10 Addition Property of Equality
3a = 330
3a _ 3 = 330 _ 3 Division Property of Equality
a = 110
So Aaronrsquos score is 110 and Alicersquos score is 2 (a - 5) = 2 (110 - 5) = 2 (105) = 210
Check that the answer makes sense
110 + 210 = 320 so the answer makes sense
B Mari Carlos and Amanda collect stamps Carlos has five more stamps than Mari and Amanda has three times as many stamps as Carlos Altogether they have 100 stamps Find the number of stamps each person has
Write a verbal description of the basic situation
Module 2 56 Lesson 2
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oug
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Mif
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cour
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pan
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Choose a variable for the unknown quantity and write an equation to model the detailed situation
Let s represent the number of stamps Mari has Then Carlos has stamps
and Amanda has stamps
s + + 3 ( ) =
Solve the equation for s
s + + 3 ( ) =
s + s + 5 + 3s + = Distributive Property
+ = Combine like terms
s = Subtraction Property of Equality
s = Division Property of Equality
So Mari has stamps Carlos has stamps and Amanda
has stamps
Check that the answer makes sense
+ + = the answer makes sense
=
Reflect
3 Would a fractional answer make sense in this situation
4 Discussion What might it mean if a check revealed that the answer to a real-world problem did not make sense
Module 2 57 Lesson 2
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arcourt Publishin
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pany
Your Turn
Write and solve an equation to solve the problem
5 A rectangular garden is fenced on all sides with 256 feet of fencing The garden is 8 feet longer than it is wide Find the length and width of the garden
Explain 2 Creating and Solving Equations with Variables on Both Sides
In some equations variables appear on both sides You can use the properties of equality to collect the variable terms so that they all appear on one side of the equation
Example 2 Write and solve an equation to solve each problem
A Janine has job offers at two companies One company offers a starting salary of $28000 with a raise of $3000 each year The other company offers a starting salary of $36000 with a raise of $2000 each year In how many years would Janinersquos salary be the same with both companies What will the salary be
Write a verbal description of the basic situation
Let n represent the number of years it takes for the salaries to be equal
Base Salary A plus $3000 per year raise = Base Salary B + $2000 per year raise
28000 + 3000n = 36000 + 2000n
28000 + 3000n - 2000n = 36000 + 2000n - 2000n Subtraction Property of Equality
28000 + 1000n = 36000 Combine like terms
28000 + 1000n - 28000 = 36000 - 28000 Subtraction Property of Equality
1000n = 8000 1000n _ 1000 = 8000 _ 1000 Division Property of Equality
n = 8
28000 + 3000 (8) = 36000 + 2000 (8)
52000 = 52000
In 8 years the salaries offered by both companies will be $52000
(w + 8) feet
w feet
Module 2 58 Lesson 2
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oug
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Mif
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Har
cour
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Com
pan
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B One moving company charges $800 plus $16 per hour Another moving company charges $720 plus $21 per hour At what number of hours will the charge by both companies be the same What is the charge
Write a verbal description of the basic situation Let t represent the number of hours that the move takes
Moving Charge A plus $16 per hour = Moving Charge B plus $21 per hour
800 + t = 720 + t
800 + t - t = 720 + t - t Subtraction Property of Equality
800 = 720 + t
800 - 720 = 720 + t - 720 Subtraction Property of Equality
= t
_ = t _
Division Property of Equality
t =
The charges are the same for a job that takes hours
Substitute the value 16 in the original equation
800 + 16t = 720 + 21t
800 + 16 ( ) = 720 + 21 ( ) 800 + = 720 +
=
After hours the moving charge for both companies will be
Reflect
6 Suppose you collected the variable terms on the other side of the equal sign to solve the equation Would that affect the solution
Module 2 59 Lesson 2
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oug
hton Mifflin H
arcourt Publishin
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pany
Your Turn
Write and solve an equation to solve each problem7 Claire bought just enough fencing to enclose either a
rectangular garden or a triangular garden as shown The two gardens have the same perimeter How many feet of fencing did she buy
8 A veterinarian is changing the diets of two animals Simba and Cuddles Simba currently consumes 1200 Calories per day That number will increase by 100 Calories each day Cuddles currently consumes 3230 Calories a day That number will decrease by 190 Calories each day The patterns will continue until both animals are consuming the same number of Calories each day In how many days will that be How many Calories will each animal be consuming each day then
Explain 3 Constructing Equations from an Organized TableYou can use a table to organize information and see relationships
Example 3 Construct and solve an equation to solve the problem
Kim works 4 hours more each day than Jill does and Jack works 2 hours less each day than Jill does Over 2 days the number of hours Kim works is equal to the difference of 4 times the number of hours Jack works and the number of hours Jill works How many hours does each person work each day
Analyze Information
Identify the important information
bull Kim works hours more per day than Jill does
bull Jack works hours less per day than Jill does
Formulate a Plan
Make a table using the information given Let x be the number of hours Jill works in one day
Hours Worked Per Day Hours Worked Over 2 Days
Kim
Jill
Jack
Over 2 days the number of hours Kim works is equal to the difference of 4 times the number of hours Jack works and the number of hours Jill works
(3x - 3)(x - 3)
(2x - 1) (2x - 1)
2x
Module 2 60 Lesson 2
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oug
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cour
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pan
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Solve
2 (x + 4) = 4 2 (x - 2) - 2x
2 (x + 4) = (x - 2) - 2x Simplify
2x + = 8x - - 2x Distributive Property
2x + 8 = x - 16
2x + 8 + = 6x - 16 + Addition Property of Equality
2x + = 6x
2x + 24 - x = 6x - x Subtraction Property of Equality
24 = x
24 _ = x _ Division Property of Equality
= x
Jill works hours per day Kim works hours per day and Jack works
hours per day
Justify and Evaluate
Substitute x = 6 into the original equation
2 (6 + 4) = 4 2 (6 - 2) - 2x
2 ( ) = 8 ( ) - 2 ( ) =
Your Turn
Write and solve an equation to solve the problem
9 Lisa is 10 centimeters taller than her friend Ian Ian is 14 centimeters taller than Jim Every month their heights increase by 2 centimeters In 7 months the sum of Ianrsquos and Jimrsquos heights will be 170 centimeters more than Lisarsquos height How tall is Ian now
Height now Height after 7 months
Module 2 61 Lesson 2
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oug
hton Mifflin H
arcourt Publishin
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pany
Elaborate
10 How can you use properties to solve equations with variables on both sides
11 How is a table helpful when constructing equations
12 When solving a real-world problem to find a personrsquos age would a negative solution make sense Explain
13 Essential Question Check-In How do you write an equation to represent a real-world situation
bull Online Homeworkbull Hints and Helpbull Extra Practice
Write an equation for each description
1 The sum of 14 and a number is equal to 17 2 A number increased by 10 is 114
3 The difference between a number and 12 is 20 4 Ten times the sum of half a number and 6 is 8
5 Two-thirds a number plus 4 is 7 6 Tanmayi wants to raise $175 for a school fundraiser She has raised $120 so far How much more does she need to reach her goal
7 Hector is visiting a cousin who lives 350 miles away He has driven 90 miles How many more miles does he need to drive to reach his cousinrsquos home
8 The length of a rectangle is twice its width The perimeter of the rectangle is 126 feet
Evaluate Homework and Practice
Module 2 62 Lesson 2
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oug
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Mif
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Har
cour
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pan
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mag
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(t)copy
Pete
r K
imS
hutt
erst
ock
Write and solve an equation for each situation
9 In one baseball season Peter hit twice the difference of the number of home runs Alice hit and 6 Altogether they hit 18 home runs How many home runs did each player hit that season
10 The perimeter of a parallelogram is 72 meters The width of the parallelogram is 4 meters less than its length Find the length and the width of the parallelogram
11 One month Ruby worked 6 hours more than Isaac and Svetlana worked 4 times as many hours as Ruby Together they worked 126 hours Find the number of hours each person worked
12 In one day Annie traveled 5 times the sum of the number of hours Brian traveled and 2 Together they traveled 20 hours Find the number of hours each person traveled
13 Xian and his cousin Kai both collect stamps Xian has 56 stamps and Kai has 80 stamps The boys recently joined different stamp-collecting clubs Xianrsquos club will send him 12 new stamps per month Kairsquos club will send him 8 new stamps per month After how many months will Xian and Kai have the same number of stamps How many stamps will each have
14 Kenya plans to make a down payment plus monthly payments in order to buy a motorcycle At one dealer she would pay $2500 down and $150 each month At another dealer she would pay $3000 down and $125 each month After how many months would the total amount paid be the same for both dealers What would that amount be
ℓ meters
(ℓ - 4) meters
Module 2 63 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
arcourt Publishin
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pany
15 Community Gym charges a $50 membership fee and a $55 monthly fee Workout Gym charges a $200 membership fee and a $45 monthly fee After how many months will the total amount of money paid to both gyms be the same What will the amount be
16 Tina is saving to buy a notebook computer She has two options The first option is to put $200 away initially and save $10 every month The second option is to put $100 away initially and save $30 every month After how many months would Tina save the same amount using either option How much would she save with either option
Use the table to answer each question
Starting Salary Yearly Salary Increase
Company A $24000 $3000
Company B $30000 $2400
Company C $36000 $2000
17 After how many years are the salaries offered by Company A and Company B the same
18 After how many years are the salaries offered by Company B and Company C the same
19 Paul started work at Company B ten years ago at the salary shown in the table At the same time Sharla started at Company C at the salary shown in the table Who earned more during the last year How much more
20 Georgersquos page contains twice as many typed words as Billrsquos page and Billrsquos page contains 50 fewer words than Charliersquos page If each person can type 60 words per minute after one minute the difference between twice the number of words on Billrsquos page and the number of words on Charliersquos page is 210 How many words did Billrsquos page contain initially Use a table to organize the information
Initial number of words
Total number of words after one minute
Module 2 64 Lesson 2
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oug
hton
Mif
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Har
cour
t Pub
lishi
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Com
pan
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21 Geometry Sammie bought just enough fencing to border either a rectangular plot or a square plot as shown The perimeters of the plots are the same How many meters of fencing did she buy
HOT Focus on Higher Order Thinking
22 Justify Reasoning Suppose you want to solve the equation 2a + b = 2a where a and b are nonzero real numbers Describe the solution to this equation Justify your description
23 Multi-step A patio in the shape of a rectangle is fenced on all sides with 134 feet of fencing The patio is 5 feet less wide than it is long
a What information can be used to solve the problem How can you find the information
b Describe how to find the area of the patio What is the area of the patio
24 Explain the Error Kevin and Brittany write an equation to represent the following relationship and both students solve their equation Who found the correct equation and solution Why is the other person incorrect
5 times the difference of a number and 20 is the same as half the sum of 4 more than 4 times a number
Kevin Brittany
5 (x - 20) = 1 _ 2 (4x + 4) 5 (20 + x) = 1 _ 2 (4x + 4)
5x - 100 = 2x + 2 100 - 5x = 2x + 2
3x - 100 = 2 100 - 7x = 2
3x = 102 -7x = -98
x = 34 x = 14
(3x + 2) meters
(x + 2) meters
(x + 2) meters
(x - 1) meters
ℓ feet
(ℓ - 5) feet
Module 2 65 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
arcourt Publishin
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pany
25 What If Alexa and Zack are solving the following problem
The number of miles on Car A is 50 miles more than the number of miles on Car B and the number of miles on Car B is 30 miles more than the number of miles on Car C All the cars travel 50 miles in 1 hour After 1 hour twice the number of miles on Car A is 70 miles less than 3 times the number of miles on Car C How many miles were there on Car B initially
Alexa assumes there are m miles on Car B Zack assumes there are m miles on Car C Will Zackrsquos answer be the same as Alexarsquos answer Explain
Lesson Performance Task
Stacy Oliver and Jivesh each plan to put a certain amount of money into their savings accounts that earn simple interest of 6 per year Stacy puts $550 more than Jivesh and Oliver puts in 2 times as much as Jivesh After a year the amount in Stacyrsquos account is 2 times the sum of $212 and the amount in Oliverrsquos account How much does each person initially put into his or her account Who had the most money in his or her account after a year Who had the least Explain
Zackrsquos Table Initial Miles
Miles after One Hour
Alexarsquos Table Initial Miles
Miles after One Hour
Amount in Account Initially Amount in Account after One Year
Module 2 66 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
hton
Mif
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Har
cour
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pan
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Name Class Date
Resource Locker
Explore Rearranging Mathematical FormulasLiteral Equations are equations that contain two or more variables There are many literal equations in the form of math science and engineering formulas These formulas may seem like they can only be solved for the variable that is isolated on one side of the formula By using inverse operations and the properties of equality a formula can be rearranged so any variable in the formula can be isolated It is no different than how equations are solved by using inverse operations and the properties of equality
How can you solve the equation 42 = 6x
A42 _ = 6x _ What is the reason for dividing
Why divide by
= x By rearranging the equation x was isolated and the solution was found
The mathematical formula for the volume of a rectangular prism B = Vh or V = ℓwh is a literal equation V represents volume ℓ represents length w represents width and h represents height Using inverse operations the formula can be rearranged to solve for any one of the variables that might be unknown Like solving for x a formula can be rearranged to isolate a variable
B In the formula V = ℓwh the variable h needs to be isolated
The operation of is used in the formula The inverse
operation should be used
to isolate
C V _____ = ℓwh _____
V _ =
The formula rearranged in this way can easily produce the height of the rectangular prism when the volume length and width are known
Reflect
1 Using the formula for a rectangular prism rewrite the formula to solve for ℓ
ℓw
h
Module 2 67 Lesson 3
23 Solving for a VariableEssential Question How do you rewrite formulas and literal equations
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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Photo
grap
hyAurora Ph
otosCorb
is
Explain 1 Rearranging Scientific FormulasUse inverse operations to isolate the unknown variable in a scientific formula
The formula for density is D = m __ V Lead has a very high density of 11340 kg m 3 Plastic foam has a very low density of 75 kg m 3 The formula for density can be rearranged to solve for V volume or m mass
Example 1
A A sinker on a fishing line is made of lead and has a volume of 0000015 m 3 What is the mass of the sinker
The density formula can be rearranged to isolate m the mass The values for volume and density can then be substituted into the formula to find the mass
D = m _ V
DV = ( m _ V ) V DV = m
(11340 kg m 3 ) (0000015 m 3 ) = m
017 kg asymp m
B The design for a life preserver requires 03 kilogram of plastic foam to provide proper buoyancy What is the volume of the plastic foam required
Rearrange the density formula to isolate V
D = m _ V
(D) V = m _ V
DV =
DV _ = m _
V =
Now substitute the given values
V = _
V = m 3
Your Turn
2 For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Determine the altitude in feet when t is -275 ∘F and g is 60 ∘F
Module 2 68 Lesson 3
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cour
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Explain 2 Rearranging Literal EquationsUsing inverse operations to rearrange literal equations can be applied to any formula The interest formula I = prt is another example of a literal equation In the formula I represents interest p the principal or the initial amount to which interest will be applied r the rate at which interest will be paid and t is the time in years
Example 2
A Find the number of years used in the calculation of a $1000 loan at an interest rate of 5 with interest totaling $600
Solve the formula for t
I = prt
I _ pr = prt
_ pr
I _ pr = t
Substitute the given values Since the interest rate is 5 r = 005$600 __
$1000 middot 005 = t
12 = t
So the length of time for the loan is 12 years
B Determine the interest rate for a $2000 loan that will be paid off in 4 years with interest totaling $640 In order to find the interest rate solve the formula for r
I = prt
I _ = prt _
_ = r
Now substitute the values and simplify
__
( ) ( ) = r
008 = r
So the interest rate is per year
Your Turn
3 The formula y = mx + b is the slope-intercept form of the equation of a line Solve the equation for m
Module 2 69 Lesson 3
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
copy H
oug
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pany
bull Online Homeworkbull Hints and Helpbull Extra Practice
Solve for the indicated variable in each mathematical formula
1 C = 2πr for r 2 A = 1 __ 2 bh for b 3 y = mx + b for x
4 A = 1 __ 2 (a + b)h for h 5 V = πr2h for h 6 SA = 2πr2 + 2πrh for h
Solve for the indicated variable in each scientific formula
7 d = rt for t 8 PV = nRT for T
9 A = FV - OV _______ T for OV 10 C = Wtc _ 1000 for W
Evaluate Homework and Practice
Elaborate
4 Discussion What could be a reason for isolating a variable in a literal equation
5 Describe a situation in which a formula could be used more easily if it were rearranged Include the formula in your description
6 Essential Question Check-In How do you isolate a variable
Module 2 70 Lesson 3
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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oug
hton
Mif
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cour
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pan
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mag
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red
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copyO
cean
C
orb
is
Solve for the indicated variable in each literal equation
11 2p + 5r = q for p 12 -10 = xy + z for x 13 a __ b = c for b
14 h - 4 _ j = k for j 15 x __ 5 - g = a for x 16 5p + 9c = p for c
17 2 __ 5 (z + 1) = y for z 18 g (h + 2 __ 3 ) = 1 for h 19 a(n - 3) + 8 = bn for n
20 Which is a possible way to rewrite the equation y = 3x + 3b to solve for b
A b = y - 3x
_ 3 C b = y - 3
_____ 3x
B b = 3(y - 3x) D b = x(y - 3)
21 Sports To find a baseball pitcherrsquos earned run average (ERA) you can use the formula Ei = 9r in which E represents ERA i represents the number of innings pitched and r represents the number of earned runs allowed Solve the equation for E What is a pitcherrsquos ERA if he allows 5 earned runs in 18 innings pitched
22 Meteorology For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Solve the equation for a If the atmospheric temperature is -655 ∘F and the ground temperature is 57 ∘F what is the altitude
Module 2 71 Lesson 3
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
arcourt Publishin
g Com
pany bull Im
age C
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Rand
y D
uch
aineA
lamy
HOT Focus on Higher Order Thinking
23 Explain the Error A student was asked to use the formula for the perimeter of a rectangle P = 2ℓ + 2w to solve for ℓ The student came up with an answer P - 2w = 2ℓ What error did the student make Explain Then solve for ℓ
24 Multi-Step The formula c = 5p + 215 relates c the total cost in dollars of hosting a birthday party at a skating rink to p the number of people attending If Alliersquos parents are willing to spend $300 for a party how many people can attend
25 Multi-Step The formula for the area of a triangle is A = 1 __ 2 bh in which b represents the length of thebase and h represents the height If a triangle has an area of 192 mm2 and the height is 12 mm what is the measure of the base
Lesson Performance TaskThe following table shows the average low temperatures in Fahrenheit for the city of Boston for several months during the year The formula F = 9 __ 5 C + 32 allows you to determine the temperature in Fahrenheit when given the temperature in Celsius
MonthTemperature in
FahrenheitTemperature in
Celsius
January 22deg
April 41deg
July 65deg
October 47deg
December 28deg
a Use the information given to determine the average low temperatures in Celsius
b Would it ever be possible for the temperature in Celsius to have a greater value than the temperature in Fahrenheit Explain why or why not
Module 2 72 Lesson 3
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
Name Class Date
Resource Locker
copy H
oug
hton
Mif
flin
Har
cour
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lishi
ng
Com
pan
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mag
e cr
edit
s copy
Patr
ick
Lan
eSo
mos
Imag
esC
orb
is
Explore Creating Inequalities from Verbal DescriptionsAn inequality is a statement that compares two expressions that are not strictly equal by using one of the following inequality signs
Symbol Meaning
lt is less than
le is less than or equal to
gt is greater than
ge is greater than or equal to
ne is not equal to
You have probably seen a sign at an amusement park saying something like ldquoYou must be at least 48 inches tall to ride this riderdquo This statement could be written as h ge 48 in where h represents the height of a person allowed to ride
Nora is planning a birthday party for her little sister Colleen Norarsquos budget will allow her to spend no more than $50 for party supplies Eight children including Colleen will attend the party and Nora wants to determine how much she could spend on party favors for each child She will also purchase a cake for $10 Write an inequality that represents the situation and find possible solutions
A First let c represent the cost of a party favor for each child Write an expression for the total cost of the party as a function of c
c +
B Which inequality symbol should be used to represent the phrase ldquono more thanrdquo
C Write the inequality that represents Norarsquos budget goal
8c + 10 le
D Suppose Nora finds party favors that cost $4 each Use a value of 4 for c and check to see if this inequality is true
8 middot 4 + 10 le 50
le 50
Module 2 73 Lesson 4
24 Creating and Solving Inequalities
Essential Question How do you write and solve an inequality that represents a real-world situation
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany
Is the inequality true
Could Nora buy $6 party favors for all of her guests without going over budget
Reflect
1 Why does an inequality represent Norarsquos budget calculation better than an equation
2 The solution set of an inequality consists of all values that make the statement true Describe the whole dollar amounts that are in the solution set for this situation
Explain 1 Creating and Solving Inequalities Involving the Distributive Property
You may need to use the Distributive Property before you can solve an inequality
Distributive Property If a b and c are real numbers then a(b + c) = ab + ac
The inequality sign must be reversed when multiplying or dividing both sides of an inequality by a negative number
Example 1
A Trina is buying 12 shirts for the drama club She will choose a style for the blank shirts and then pay an additional charge of $275 for each shirt to have the club logo If Trina cannot spend more than $99 how much can she spend on each blank shirt Write and solve an inequality to find the possible cost of each blank shirt
Let s represent the cost of each blank shirt
Write an inequality to represent the situation 12(s + 275) le 99
Use the Distributive Property 12s + 33 le 99
Subtraction Property of Inequality 12s + 33 - 33 le 99 - 33
Simplify 12s le 66
Division Property of Inequality 12s ___ 12 le 66 __ 12
Simplify s le 55
Module 2 74 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
copy H
oug
hton
Mif
flin
Har
cour
t Pub
lishi
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Com
pan
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Check your answer
Since s le 55 check a smaller number 12(5 + 275) le 99
Trina can order blank shirts that cost $550 or less 93 le 99 true
B Sergio needs to buy gifts for 8 friends He wants to give the same gift to all his friends and he plans to have the gifts wrapped for an additional charge of $150 each If Sergio spends at least $70 he will receive free shipping on his order Write and solve an inequality to determine how much Sergio needs to spend on each gift in order to receive free shipping
Let g be the cost of one gift
Write an inequality to represent the situation ( g + ) ge 70
Use the Distributive Property g + ge 70
Subtraction Property of Inequality g + 12 - ge 70 -
Simplify 8g ge
Division Property of Inequality 8g _
ge 58 _
Simplify g ge
Check your answer
Since g ge 725 check a larger number 8(8 + 150) ge 70
Sergio must spend at least on each gift ge 70
Reflect
3 Discussion Why is the first step in solving the inequality to use the Distributive Property instead of working inside the parentheses
Your Turn
4 Zachary is planning to send a video game to each of his two brothers If he buys the same game for both brothers and pays $475 to ship each game how much can he spend on each game without spending more than $100 Write and solve an inequality for this situation
Solve each inequality
5 4 _ 3 (6x + 9) lt 4 6 -2 ( 1 _ 4 x + 2 ) ge 5
Module 2 75 Lesson 4
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pany
Explain 2 Creating and Solving Inequalities with Variables on Both Sides
Some inequalities have variable terms on both sides of the inequality symbol You can solve these inequalities the same way you solved equations with variables on both sides Use the properties of inequality to collect all the variable terms on one side and all the constant terms on the other side
Example 2
A The Daily Info charges a fee of $650 plus $80 per week to run an ad The Peoplersquos Paper charges $145 per week For how many weeks must an ad run for the total cost at the Daily Info to be less expensive than the cost at the Peoplersquos Paper Let w be the number of weeks the ad runs in the paper
Write an inequality to represent the situation 650 + 80w lt 145w
Subtraction Property of Inequality 650 + 80w - 80w lt 145w - 80w
Simplify 650 lt 65w
Division Property of Inequality 650 _ 65 lt 65w _ 65
Simplify 10 lt w
The total cost at the Daily Info is less than the cost at the Peoplersquos Paper if the ad runs for more than 10 weeks
B The Home Cleaning Company charges $312 to power-wash the siding of a house plus $12 for each window Power Clean charges $36 per window and the price includes power-washing the siding How many windows must a house have to make the total cost from The Home Cleaning Company less expensive than Power Clean Let w be the number of windows
Write an inequality to represent the situation +12w lt 36w
Subtraction Property of Inequality 312 + 12w - lt 36w -
Simplify 312 lt
Division Property of Inequality 312 _ lt 24w _
Simplify lt w
A house must have more than 13 windows for The Home Cleaning Company to be less expensive than Power Clean
Reflect
7 How would the final inequality change if you divided by ndash24 in the next to last step
Your Turn
8 The school band will sell pizzas to raise money for new uniforms The supplier charges $100 plus $4 per pizza The band members sell the pizzas for $7 each Write and solve an inequality to find how many pizzas the band members will have to sell to make a profit
Module 2 76 Lesson 4
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Elaborate
9 Which inequality symbol would you use to represent the following words or phrases Can you come up with more examples
a at most b farther than c younger than d up to
10 Discussion How are the steps to solving an inequality similar to those for solving an equation How are they different
11 Essential Question Check-In How can you write an inequality that represents a real-world situation
Write an inequality that represents the description and then solve
1 Max has more than 5 carrots (number of carrots Max has = c)
2 Brigitte is shorter than 5 feet (Brigittersquos height = h)
3 Twice a number (x) is less than 10 4 Six more than five times a number (x) is at least twenty-one
5 Dave has $15 to spend on an $8 book and two birthday cards (c) for his friends How much can he spend on each card if he buys the same card for each friend
6 Toni can carry up to 18 lb in her backpack Her lunch weighs 1 lb her gym clothes weigh 2 lb and her books (b) weigh 3 lb each How many books can she carry in her backpack
Evaluate Homework and Practice
bull Online Homeworkbull Hints and Helpbull Extra Practice
Module 2 77 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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pany
Solve each inequality
7 3 (x - 2) gt -3 8 5 + 5 (x + 4) le 20 9 3 + 1 _ 2 (3 - x) lt -7
10 3 (x + 6) - 2 (x + 2) ge 10 11 5 (3 - x) -4 (2 - 3x) gt 2 12 1 _ 2 (4x - 2) - 2 _ 3 (6x + 9) le 4
13 x + 1 gt -5 (7 - 2x) 14 5 _ 3 (6x + 3) le 2x - 7
15 2x le - 2 __ 3 (4x + 4) 16 1 __ 2 (-2x - 10) gt 3 (4 - 6x)
17 -5 - 3x ge 2 (10 + 2x) + 3 18 -3 (9x + 20) ge 15x - 20
19 8 ( 1 _ 4 x - 3) + 24 lt 4 ( x + 5 ) 20 6x - 2 (x + 2) gt 2 - 3 (x + 3)
Module 2 78 Lesson 4
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21 Physics A crane cable can support a maximum load of 15000 kg If a bucket has a mass of 2000 kg and gravel has a mass of 1500 kg for every cubic meter how many cubic meters of gravel (g) can be safely lifted by the crane
22 Find the solution set of each inequality below and then determine which inequalities have the same solution set as 1 _ 3 ( -5x - 3 ) lt 14
a 1 _ 3 (5x + 3) gt -14 b 2 _ 5 (10x + 20) gt 44
c - 2 _ 5 (10x + 20) lt -44 d - 1 _ 3 (5x + 3) lt 14
e 2 _ 5 (10x - 20) gt -44 f 1 _ 3 (5x + 3) lt -14
HOT Focus on Higher Order Thinking
23 Explain the Error Sven is trying to find the maximum amount of time he can spend practicing the five scales of piano music he is supposed to be working on He has 60 minutes to practice piano and would like to spend at least 35 minutes playing songs instead of practicing scales So Sven sets up the following inequality where t is the number of minutes he spends on each scale and solves it
60 - 5t le 35-5t le -25
t ge 5
Sven has concluded that he should spend 5 minutes or more on each scale Is this correct If not what mistake did he make Then solve for the correct answer
Module 2 79 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
24 Critical Thinking Anika wants to determine the maximum number of tulip bulbs (t) she can purchase if each bulb costs $150 She will also need to purchase separate pots for each bulb at $125 each and a bag of potting soil for $1000 Set up an inequality to determine how many tulip bulbs Anika can purchase without spending more than $2000 and solve it Can Anika buy exactly enough bulbs and pots to spend the full $2000 Explain Can you think of a better inequality to describe the answer
25 Geometry The area of the triangle shown is no more than 10 square inches
a Write an inequality that can be used to find x
b Solve the inequality from part a c What is the maximum height of the triangle
Lesson Performance TaskWhen planning an airplane route the trip planner must be careful to consider the range the aircraft can travel and the availability of airports to stop and refuel
A large commercial jet airplane burns approximately 5 gallons of fuel per mile flown plus about 8500 gallons of fuel per trip to reach cruising altitude With a useable fuel capacity of 50000 gallons (there is additional fuel reserved for emergencies) describe the acceptable distance for which an airline could establish a non-stop flight
For flights originating from Chicago determine which cities could be safely reached by a non-stop flight
City Distance from Chicago (miles)
Bangalore India 8530
Jakarta Indonesia 9810
Johannesburg South Africa 8680
Moscow Russia 4970
Paris France 4130
Perth Australia 10970
Tokyo Japan 6300
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oug
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its copySarych
eva O
lesiaShutterstock
(2x - 3) in
4 in
Module 2 80 Lesson 4
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Name Class Date
Resource Locker
Explore Truth Tables and Compound StatementsA compound statement is formed by combining two or more simple statements A compound statement can be true or false A compound statement involving AND is true when both simple statements are true A compound statement involving OR is true when either one simple statement or both are true
A Complete the truth table
P QP
True or FalseQ
True or FalseP AND Q
True or False
A dog is a mammal Red is a color
A dog is a mammal Red is not a color
A dog is a fish Red is a color
A dog is a fish Red is not a color
B P AND Q is true when
C Complete the truth table
P QP
True or FalseQ
True or FalseP OR Q
True or False
1 is an odd number 2 is an even number
1 is an odd number 2 is an odd number
1 is an even number 2 is an even number
1 is an even number 2 is an odd number
D P OR Q is true when
Reflect
1 Give two simple statements P and Q for which P AND Q is false and P OR Q is true
Module 2 81 Lesson 5
25 Creating and Solving Compound Inequalities
Essential Question How can you solve a compound inequality and graph the solution set
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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arcourt Publishin
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pany
Explain 1 Solving Compound Inequalities Involving ANDCombining two or more simple inequalities forms a compound inequality The graph of a compound inequality involving AND is the intersection or the overlapping region of the simple inequality graphs
Compound Inequalities AND
Words Algebra Graph
All real numbers greater than 2AND less than 6
x gt 2 AND x lt 62 lt x lt 6
All real numbers greater than or equal to 2 AND less than or equal to 6
x ge 2 AND x le 62 le x le 6
Example 1 Solve each compound inequality and graph the solutions
A 4 le x + 2 le 8
4 le x + 2 AND x + 2 le 8 Write the compound inequality using AND
4 - 2 le x + 2 - 2 x + 2 - 2 le 8 - 2 Subtract 2 from both sides of each simple inequality
2 le x x le 6 Simplify
Graph 2 le x
Graph x le 6
Graph the intersection by finding where the two graphs overlap
B -5 le 2x + 3 lt 9
-5 - le 2x + 3 - lt 9 - Subtract from each part of the inequality
le 2x lt Simplify
-8 _ le 2x _ lt 6 _ Divide each part of the inequality by
le x lt Simplify
Graph -4 le x
Graph x lt 3
Graph the intersection by finding where the two graphs overlap -1 0 1 2 3 4 5-5-4 -3 -2
0 2 4 6 8 10 12-8-6-4 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 82 Lesson 5
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Reflect
2 Discussion Explain why 2 le x le 6 can be considered the short method for writing the AND compound inequality x ge 2 AND x le 6
YourTurn
Solve each compound inequality and graph the solutions
3 -2 lt x - 3 lt 5
4 -10 lt 3x + 2 le 8
Explain 2 Solving Compound Inequalities Involving ORThe graph of a compound inequality involving OR is the union or the combined region of the simple inequality graphs
Compound Inequalities OR
Words Algebra Graph
All real numbers less than 2OR greater than 6
x lt 2 OR x gt 6
All real numbers less than or equal to 2OR greater than or equal to 6
x le 2 OR x ge 6
-1 0 1 2 3 4 5-5-4 -3 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 83 Lesson 5
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oug
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Example 2 Solve each compound inequality and graph the solutions
A -4 + x gt 1 OR -4 + x lt -3
-4 + x gt 1 OR -4 + x lt -3 Write the compound inequality using OR
-4 + 4 + x gt 1 + 4 -4 + 4 + x lt -3 + 4 Add 4 to both sides of each simple inequality
x gt 5 x lt 1 Simplify
Graph x gt 5
Graph x lt 1
Graph the union by combining the graphs
B 2x le 6 OR 3x gt 12
2x le 6 OR 3x gt 12 Write the compound inequality using OR
2x _ le 6 _ OR 3x _ gt 12 _ Divide the first simple inequality by
x le OR x gt
Graph x le 3
Graph x gt 4
Graph the union by combining the graphs
Reflect
5 Critical Thinking What kind of compound inequality has no solution
Divide the second simple inequality by
Simplify
0 1 2 3 4 5 6-4 -3 -2 -1
-0 1 2 3 4 5 6-4 -3 -2 -1
Module 2 84 Lesson 5
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oug
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Your Turn
Solve each compound inequality and graph the solutions
6 x - 5 ge -2 OR x -5 le -6
7 4x -1 lt 15 OR 8x ge 48
Explain 3 Creating Compound Inequalities From GraphsGiven a number line graph with a solution set graphed you can create a compound inequality to fit the graph
Example 3 Write the compound inequality shown by each graph
A
The shaded portion of the graph is not between two values so the compound inequality involves OR
On the left the graph shows an arrow pointing left from -1 and a solid circle so use le
The inequality is x le -1
On the right the graph shows an arrow pointing right from 7 and a solid circle so use ge
The inequality is x ge 7
The compound inequality is x le -1 OR x ge 7
B
The graph is shaded between the values and so the compound inequality involves AND
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The compound inequality is
-1 0 1 2 3 4 5-5-4 -3 -2
4 5 6 7 8 9 100 1 2 3
2 3 4 5 6 7 8-2 -1 0 1
10 2 3 4 5 6 7 8 9-1
Module 2 85 Lesson 5
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oug
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pany
Reflect
8 What is a short method to write the compound inequality x ge 0 AND x lt 6
Your Turn
Write the compound inequality shown by each graph
9
10
Explain 4 Expressing Acceptable Levels with Compound Inequalities
You can express quality-controls levels in real-world problems using compound inequalities
Example 4 Write a compound inequality to represent the indicated quality-control level and graph the solutions
A The recommended pH level for swimming pool water is between 72 and 76 inclusive
Let p be the pH level of swimming pool water
72 is less than or equal to pH level is less than or equal to 76
72 le p le 76
The compound inequality is 72 le p le 76
Graph the solutions
0-10 -8-9 -7-6 -5-4 -3 -2 -1
71 72 73 74 75 76 77 78 79 8070
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 86 Lesson 5
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oug
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B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
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oug
hton Mifflin H
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pany
bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
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Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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arcourt Publishin
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age C
redits copy
Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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Mif
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Har
cour
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Com
pan
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mag
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copy
bik
erid
erlo
nd
onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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cour
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Com
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mag
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copyJe
ssie
W
alke
rLi
ved
In Im
ages
Cor
bis
Suppose a and b give the populations of two states where a gt b Compare the expressions and tell which of the given pair is greater or if the expressions are equal
15 b _ a + b
and 05
16 a + 13c and b + 13c where c is the population of a third state
17 a - b _ 2 and a - b _ 2
18 a + b and 2b
19 5(a + b) and (a + b)5
Write an algebraic expression to model the given context Give your answer in simplest form
20 the price s of a pair of shoes plus 5 sales tax 21 the original price p of an item less a discount of 20
22 the price h of a recently bought house plus 10 property tax
23 the principal amount P originally deposited in a bank account plus 03 interest
Module 2 51 Lesson 1
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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pany
24 Match each statement with the algebraic expression that models it
A the price of a winter coat and a 20 discount x + 002x = 102x
B the base salary of an employee and a 2 salary increase x - 020x = 080x
C the cost of groceries and a 2 discount with coupons x + 020x = 120x
D the number of students attending school last year and a 20 increase from last year x - 002x = 098x
HOT Focus on Higher Order Thinking
25 Critique Reasoning A student is given the rectangle and the square shown The student states that the two figures have the same perimeter Is the student correct Explain your reasoning
26 Multi-Step Yon buys tickets to a concert for himself and a friend There is a tax of 6 on the price of the tickets and an additional booking fee of $20 for the transaction Write an algebraic expression to represent the price per person Simplify the expression if possible
x + 2
x + 2x
x + 4
Module 2 52 Lesson 1
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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27 Persevere in Problem Solving Jerry is planting white daisies and red tulips in his garden and he wants to choose a pattern in which the tulips surround the daisies He uses tiles to generate patterns starting with two rows of three daisies He surrounds these daisies with a border of tulips The design continues as shown
a Jerry writes the expression 8(b - 1) + 10 for the number of tulips in each border wherein b is the border number and b ge 1 Explain why Jerryrsquos expression is correct
b Elaine wants to start with two rows of four daisies Her reasoning is that Jerry started with two rows of three daisies and his expression was 8(b - 1) + 10 so if she starts with two rows of four daisies her expression will be 10(b - 1) + 10 Is Elainersquos statement correct Explain
Border 1 Border 2 Border 3
Module 2 53 Lesson 1
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
Lesson Performance Task
Becky and Michele are both shopping for a new car at two different dealerships Dealership A is offering $500 cash back on any purchase while Dealership B is offering $1000 cash back The tax rate is 5 at Dealership A but 8 at Dealership B Becky wants to buy a car that is $15000 and Michele is planning to buy a car that costs $20000 Use algebraic expressions to help you answer the following questions
a At which dealership will Becky get the better deal How much does she save
b At which dealership will Michele get the better deal How much does she save
c What generalization can you make that would help any shopper know which dealership has the better deal [Hint At what price point would the two deals be equal]
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oug
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redits copy
Tom G
rillC
orbis
Module 2 54 Lesson 1
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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Name Class Date
Resource Locker
Explore Creating Equations from Verbal Descriptions
You can use what you know about writing algebraic expressions to write an equation that represents a real-world situation
Suppose Cory and his friend Walter go to a movie Each of their tickets costs the same amount and they share a frozen yogurt that costs $550 The total amount they spend is $1990 How can you write an equation that describes the situation
A Identify the important information
The word tells you that the relationship describes an equation
The word total tells you that the operation involved in the relationship is
What numerical information do you have
What is the unknown quantity
B Write a verbal description
Choose a name for the variable In this case use c for
The verbal description is Twice the cost of plus the cost
of equals
C To write an equation write a numerical or expression for each quantity
and insert an equal sign in the appropriate place An equation is
Reflect
1 How can you use a verbal model to write an equation for the situation described
Module 2 55 Lesson 2
22 Creating and Solving EquationsEssential Question How do you use an equation to model and solve a real-world problem
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igital
Vision
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ages
2 Could you write a different equation to describe the situation Explain your reasoning
Explain 1 Creating and Solving Equations Involving the Distributive Property
When you create an equation to model a real-world problem your equation may involve the Distributive Property When you solve a real-world problem you should always check that your answer makes sense
Example 1 Write and solve an equation to solve each problem
A Aaron and Alice are bowling Alicersquos score is twice the difference of Aaronrsquos score and 5 The sum of their scores is 320 Find each studentrsquos bowling score
Write a verbal description of the basic situation
The sum of Aaronrsquos score and Alicersquos score is 320
Choose a variable for the unknown quantity and write an equation to model the detailed situation
Let a represent Aaronrsquos score Then 2 (a - 5) represents Alicersquos score
a + 2 (a - 5) = 320
Solve the equation for a
a + 2 (a - 5) = 320
a + 2a - 10 = 320 Distributive Property
3a - 10 = 320
3a - 10 + 10 = 320 + 10 Addition Property of Equality
3a = 330
3a _ 3 = 330 _ 3 Division Property of Equality
a = 110
So Aaronrsquos score is 110 and Alicersquos score is 2 (a - 5) = 2 (110 - 5) = 2 (105) = 210
Check that the answer makes sense
110 + 210 = 320 so the answer makes sense
B Mari Carlos and Amanda collect stamps Carlos has five more stamps than Mari and Amanda has three times as many stamps as Carlos Altogether they have 100 stamps Find the number of stamps each person has
Write a verbal description of the basic situation
Module 2 56 Lesson 2
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pan
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Choose a variable for the unknown quantity and write an equation to model the detailed situation
Let s represent the number of stamps Mari has Then Carlos has stamps
and Amanda has stamps
s + + 3 ( ) =
Solve the equation for s
s + + 3 ( ) =
s + s + 5 + 3s + = Distributive Property
+ = Combine like terms
s = Subtraction Property of Equality
s = Division Property of Equality
So Mari has stamps Carlos has stamps and Amanda
has stamps
Check that the answer makes sense
+ + = the answer makes sense
=
Reflect
3 Would a fractional answer make sense in this situation
4 Discussion What might it mean if a check revealed that the answer to a real-world problem did not make sense
Module 2 57 Lesson 2
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Your Turn
Write and solve an equation to solve the problem
5 A rectangular garden is fenced on all sides with 256 feet of fencing The garden is 8 feet longer than it is wide Find the length and width of the garden
Explain 2 Creating and Solving Equations with Variables on Both Sides
In some equations variables appear on both sides You can use the properties of equality to collect the variable terms so that they all appear on one side of the equation
Example 2 Write and solve an equation to solve each problem
A Janine has job offers at two companies One company offers a starting salary of $28000 with a raise of $3000 each year The other company offers a starting salary of $36000 with a raise of $2000 each year In how many years would Janinersquos salary be the same with both companies What will the salary be
Write a verbal description of the basic situation
Let n represent the number of years it takes for the salaries to be equal
Base Salary A plus $3000 per year raise = Base Salary B + $2000 per year raise
28000 + 3000n = 36000 + 2000n
28000 + 3000n - 2000n = 36000 + 2000n - 2000n Subtraction Property of Equality
28000 + 1000n = 36000 Combine like terms
28000 + 1000n - 28000 = 36000 - 28000 Subtraction Property of Equality
1000n = 8000 1000n _ 1000 = 8000 _ 1000 Division Property of Equality
n = 8
28000 + 3000 (8) = 36000 + 2000 (8)
52000 = 52000
In 8 years the salaries offered by both companies will be $52000
(w + 8) feet
w feet
Module 2 58 Lesson 2
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oug
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cour
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pan
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B One moving company charges $800 plus $16 per hour Another moving company charges $720 plus $21 per hour At what number of hours will the charge by both companies be the same What is the charge
Write a verbal description of the basic situation Let t represent the number of hours that the move takes
Moving Charge A plus $16 per hour = Moving Charge B plus $21 per hour
800 + t = 720 + t
800 + t - t = 720 + t - t Subtraction Property of Equality
800 = 720 + t
800 - 720 = 720 + t - 720 Subtraction Property of Equality
= t
_ = t _
Division Property of Equality
t =
The charges are the same for a job that takes hours
Substitute the value 16 in the original equation
800 + 16t = 720 + 21t
800 + 16 ( ) = 720 + 21 ( ) 800 + = 720 +
=
After hours the moving charge for both companies will be
Reflect
6 Suppose you collected the variable terms on the other side of the equal sign to solve the equation Would that affect the solution
Module 2 59 Lesson 2
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Your Turn
Write and solve an equation to solve each problem7 Claire bought just enough fencing to enclose either a
rectangular garden or a triangular garden as shown The two gardens have the same perimeter How many feet of fencing did she buy
8 A veterinarian is changing the diets of two animals Simba and Cuddles Simba currently consumes 1200 Calories per day That number will increase by 100 Calories each day Cuddles currently consumes 3230 Calories a day That number will decrease by 190 Calories each day The patterns will continue until both animals are consuming the same number of Calories each day In how many days will that be How many Calories will each animal be consuming each day then
Explain 3 Constructing Equations from an Organized TableYou can use a table to organize information and see relationships
Example 3 Construct and solve an equation to solve the problem
Kim works 4 hours more each day than Jill does and Jack works 2 hours less each day than Jill does Over 2 days the number of hours Kim works is equal to the difference of 4 times the number of hours Jack works and the number of hours Jill works How many hours does each person work each day
Analyze Information
Identify the important information
bull Kim works hours more per day than Jill does
bull Jack works hours less per day than Jill does
Formulate a Plan
Make a table using the information given Let x be the number of hours Jill works in one day
Hours Worked Per Day Hours Worked Over 2 Days
Kim
Jill
Jack
Over 2 days the number of hours Kim works is equal to the difference of 4 times the number of hours Jack works and the number of hours Jill works
(3x - 3)(x - 3)
(2x - 1) (2x - 1)
2x
Module 2 60 Lesson 2
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Solve
2 (x + 4) = 4 2 (x - 2) - 2x
2 (x + 4) = (x - 2) - 2x Simplify
2x + = 8x - - 2x Distributive Property
2x + 8 = x - 16
2x + 8 + = 6x - 16 + Addition Property of Equality
2x + = 6x
2x + 24 - x = 6x - x Subtraction Property of Equality
24 = x
24 _ = x _ Division Property of Equality
= x
Jill works hours per day Kim works hours per day and Jack works
hours per day
Justify and Evaluate
Substitute x = 6 into the original equation
2 (6 + 4) = 4 2 (6 - 2) - 2x
2 ( ) = 8 ( ) - 2 ( ) =
Your Turn
Write and solve an equation to solve the problem
9 Lisa is 10 centimeters taller than her friend Ian Ian is 14 centimeters taller than Jim Every month their heights increase by 2 centimeters In 7 months the sum of Ianrsquos and Jimrsquos heights will be 170 centimeters more than Lisarsquos height How tall is Ian now
Height now Height after 7 months
Module 2 61 Lesson 2
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oug
hton Mifflin H
arcourt Publishin
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pany
Elaborate
10 How can you use properties to solve equations with variables on both sides
11 How is a table helpful when constructing equations
12 When solving a real-world problem to find a personrsquos age would a negative solution make sense Explain
13 Essential Question Check-In How do you write an equation to represent a real-world situation
bull Online Homeworkbull Hints and Helpbull Extra Practice
Write an equation for each description
1 The sum of 14 and a number is equal to 17 2 A number increased by 10 is 114
3 The difference between a number and 12 is 20 4 Ten times the sum of half a number and 6 is 8
5 Two-thirds a number plus 4 is 7 6 Tanmayi wants to raise $175 for a school fundraiser She has raised $120 so far How much more does she need to reach her goal
7 Hector is visiting a cousin who lives 350 miles away He has driven 90 miles How many more miles does he need to drive to reach his cousinrsquos home
8 The length of a rectangle is twice its width The perimeter of the rectangle is 126 feet
Evaluate Homework and Practice
Module 2 62 Lesson 2
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oug
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Har
cour
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pan
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mag
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(t)copy
Pete
r K
imS
hutt
erst
ock
Write and solve an equation for each situation
9 In one baseball season Peter hit twice the difference of the number of home runs Alice hit and 6 Altogether they hit 18 home runs How many home runs did each player hit that season
10 The perimeter of a parallelogram is 72 meters The width of the parallelogram is 4 meters less than its length Find the length and the width of the parallelogram
11 One month Ruby worked 6 hours more than Isaac and Svetlana worked 4 times as many hours as Ruby Together they worked 126 hours Find the number of hours each person worked
12 In one day Annie traveled 5 times the sum of the number of hours Brian traveled and 2 Together they traveled 20 hours Find the number of hours each person traveled
13 Xian and his cousin Kai both collect stamps Xian has 56 stamps and Kai has 80 stamps The boys recently joined different stamp-collecting clubs Xianrsquos club will send him 12 new stamps per month Kairsquos club will send him 8 new stamps per month After how many months will Xian and Kai have the same number of stamps How many stamps will each have
14 Kenya plans to make a down payment plus monthly payments in order to buy a motorcycle At one dealer she would pay $2500 down and $150 each month At another dealer she would pay $3000 down and $125 each month After how many months would the total amount paid be the same for both dealers What would that amount be
ℓ meters
(ℓ - 4) meters
Module 2 63 Lesson 2
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oug
hton Mifflin H
arcourt Publishin
g Com
pany
15 Community Gym charges a $50 membership fee and a $55 monthly fee Workout Gym charges a $200 membership fee and a $45 monthly fee After how many months will the total amount of money paid to both gyms be the same What will the amount be
16 Tina is saving to buy a notebook computer She has two options The first option is to put $200 away initially and save $10 every month The second option is to put $100 away initially and save $30 every month After how many months would Tina save the same amount using either option How much would she save with either option
Use the table to answer each question
Starting Salary Yearly Salary Increase
Company A $24000 $3000
Company B $30000 $2400
Company C $36000 $2000
17 After how many years are the salaries offered by Company A and Company B the same
18 After how many years are the salaries offered by Company B and Company C the same
19 Paul started work at Company B ten years ago at the salary shown in the table At the same time Sharla started at Company C at the salary shown in the table Who earned more during the last year How much more
20 Georgersquos page contains twice as many typed words as Billrsquos page and Billrsquos page contains 50 fewer words than Charliersquos page If each person can type 60 words per minute after one minute the difference between twice the number of words on Billrsquos page and the number of words on Charliersquos page is 210 How many words did Billrsquos page contain initially Use a table to organize the information
Initial number of words
Total number of words after one minute
Module 2 64 Lesson 2
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oug
hton
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Har
cour
t Pub
lishi
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Com
pan
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21 Geometry Sammie bought just enough fencing to border either a rectangular plot or a square plot as shown The perimeters of the plots are the same How many meters of fencing did she buy
HOT Focus on Higher Order Thinking
22 Justify Reasoning Suppose you want to solve the equation 2a + b = 2a where a and b are nonzero real numbers Describe the solution to this equation Justify your description
23 Multi-step A patio in the shape of a rectangle is fenced on all sides with 134 feet of fencing The patio is 5 feet less wide than it is long
a What information can be used to solve the problem How can you find the information
b Describe how to find the area of the patio What is the area of the patio
24 Explain the Error Kevin and Brittany write an equation to represent the following relationship and both students solve their equation Who found the correct equation and solution Why is the other person incorrect
5 times the difference of a number and 20 is the same as half the sum of 4 more than 4 times a number
Kevin Brittany
5 (x - 20) = 1 _ 2 (4x + 4) 5 (20 + x) = 1 _ 2 (4x + 4)
5x - 100 = 2x + 2 100 - 5x = 2x + 2
3x - 100 = 2 100 - 7x = 2
3x = 102 -7x = -98
x = 34 x = 14
(3x + 2) meters
(x + 2) meters
(x + 2) meters
(x - 1) meters
ℓ feet
(ℓ - 5) feet
Module 2 65 Lesson 2
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oug
hton Mifflin H
arcourt Publishin
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pany
25 What If Alexa and Zack are solving the following problem
The number of miles on Car A is 50 miles more than the number of miles on Car B and the number of miles on Car B is 30 miles more than the number of miles on Car C All the cars travel 50 miles in 1 hour After 1 hour twice the number of miles on Car A is 70 miles less than 3 times the number of miles on Car C How many miles were there on Car B initially
Alexa assumes there are m miles on Car B Zack assumes there are m miles on Car C Will Zackrsquos answer be the same as Alexarsquos answer Explain
Lesson Performance Task
Stacy Oliver and Jivesh each plan to put a certain amount of money into their savings accounts that earn simple interest of 6 per year Stacy puts $550 more than Jivesh and Oliver puts in 2 times as much as Jivesh After a year the amount in Stacyrsquos account is 2 times the sum of $212 and the amount in Oliverrsquos account How much does each person initially put into his or her account Who had the most money in his or her account after a year Who had the least Explain
Zackrsquos Table Initial Miles
Miles after One Hour
Alexarsquos Table Initial Miles
Miles after One Hour
Amount in Account Initially Amount in Account after One Year
Module 2 66 Lesson 2
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oug
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cour
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pan
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Name Class Date
Resource Locker
Explore Rearranging Mathematical FormulasLiteral Equations are equations that contain two or more variables There are many literal equations in the form of math science and engineering formulas These formulas may seem like they can only be solved for the variable that is isolated on one side of the formula By using inverse operations and the properties of equality a formula can be rearranged so any variable in the formula can be isolated It is no different than how equations are solved by using inverse operations and the properties of equality
How can you solve the equation 42 = 6x
A42 _ = 6x _ What is the reason for dividing
Why divide by
= x By rearranging the equation x was isolated and the solution was found
The mathematical formula for the volume of a rectangular prism B = Vh or V = ℓwh is a literal equation V represents volume ℓ represents length w represents width and h represents height Using inverse operations the formula can be rearranged to solve for any one of the variables that might be unknown Like solving for x a formula can be rearranged to isolate a variable
B In the formula V = ℓwh the variable h needs to be isolated
The operation of is used in the formula The inverse
operation should be used
to isolate
C V _____ = ℓwh _____
V _ =
The formula rearranged in this way can easily produce the height of the rectangular prism when the volume length and width are known
Reflect
1 Using the formula for a rectangular prism rewrite the formula to solve for ℓ
ℓw
h
Module 2 67 Lesson 3
23 Solving for a VariableEssential Question How do you rewrite formulas and literal equations
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oug
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arcourt Publishin
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Photo
grap
hyAurora Ph
otosCorb
is
Explain 1 Rearranging Scientific FormulasUse inverse operations to isolate the unknown variable in a scientific formula
The formula for density is D = m __ V Lead has a very high density of 11340 kg m 3 Plastic foam has a very low density of 75 kg m 3 The formula for density can be rearranged to solve for V volume or m mass
Example 1
A A sinker on a fishing line is made of lead and has a volume of 0000015 m 3 What is the mass of the sinker
The density formula can be rearranged to isolate m the mass The values for volume and density can then be substituted into the formula to find the mass
D = m _ V
DV = ( m _ V ) V DV = m
(11340 kg m 3 ) (0000015 m 3 ) = m
017 kg asymp m
B The design for a life preserver requires 03 kilogram of plastic foam to provide proper buoyancy What is the volume of the plastic foam required
Rearrange the density formula to isolate V
D = m _ V
(D) V = m _ V
DV =
DV _ = m _
V =
Now substitute the given values
V = _
V = m 3
Your Turn
2 For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Determine the altitude in feet when t is -275 ∘F and g is 60 ∘F
Module 2 68 Lesson 3
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oug
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Mif
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Har
cour
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Com
pan
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Explain 2 Rearranging Literal EquationsUsing inverse operations to rearrange literal equations can be applied to any formula The interest formula I = prt is another example of a literal equation In the formula I represents interest p the principal or the initial amount to which interest will be applied r the rate at which interest will be paid and t is the time in years
Example 2
A Find the number of years used in the calculation of a $1000 loan at an interest rate of 5 with interest totaling $600
Solve the formula for t
I = prt
I _ pr = prt
_ pr
I _ pr = t
Substitute the given values Since the interest rate is 5 r = 005$600 __
$1000 middot 005 = t
12 = t
So the length of time for the loan is 12 years
B Determine the interest rate for a $2000 loan that will be paid off in 4 years with interest totaling $640 In order to find the interest rate solve the formula for r
I = prt
I _ = prt _
_ = r
Now substitute the values and simplify
__
( ) ( ) = r
008 = r
So the interest rate is per year
Your Turn
3 The formula y = mx + b is the slope-intercept form of the equation of a line Solve the equation for m
Module 2 69 Lesson 3
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oug
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arcourt Publishin
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bull Online Homeworkbull Hints and Helpbull Extra Practice
Solve for the indicated variable in each mathematical formula
1 C = 2πr for r 2 A = 1 __ 2 bh for b 3 y = mx + b for x
4 A = 1 __ 2 (a + b)h for h 5 V = πr2h for h 6 SA = 2πr2 + 2πrh for h
Solve for the indicated variable in each scientific formula
7 d = rt for t 8 PV = nRT for T
9 A = FV - OV _______ T for OV 10 C = Wtc _ 1000 for W
Evaluate Homework and Practice
Elaborate
4 Discussion What could be a reason for isolating a variable in a literal equation
5 Describe a situation in which a formula could be used more easily if it were rearranged Include the formula in your description
6 Essential Question Check-In How do you isolate a variable
Module 2 70 Lesson 3
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oug
hton
Mif
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Har
cour
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Com
pan
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mag
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red
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copyO
cean
C
orb
is
Solve for the indicated variable in each literal equation
11 2p + 5r = q for p 12 -10 = xy + z for x 13 a __ b = c for b
14 h - 4 _ j = k for j 15 x __ 5 - g = a for x 16 5p + 9c = p for c
17 2 __ 5 (z + 1) = y for z 18 g (h + 2 __ 3 ) = 1 for h 19 a(n - 3) + 8 = bn for n
20 Which is a possible way to rewrite the equation y = 3x + 3b to solve for b
A b = y - 3x
_ 3 C b = y - 3
_____ 3x
B b = 3(y - 3x) D b = x(y - 3)
21 Sports To find a baseball pitcherrsquos earned run average (ERA) you can use the formula Ei = 9r in which E represents ERA i represents the number of innings pitched and r represents the number of earned runs allowed Solve the equation for E What is a pitcherrsquos ERA if he allows 5 earned runs in 18 innings pitched
22 Meteorology For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Solve the equation for a If the atmospheric temperature is -655 ∘F and the ground temperature is 57 ∘F what is the altitude
Module 2 71 Lesson 3
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
arcourt Publishin
g Com
pany bull Im
age C
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Rand
y D
uch
aineA
lamy
HOT Focus on Higher Order Thinking
23 Explain the Error A student was asked to use the formula for the perimeter of a rectangle P = 2ℓ + 2w to solve for ℓ The student came up with an answer P - 2w = 2ℓ What error did the student make Explain Then solve for ℓ
24 Multi-Step The formula c = 5p + 215 relates c the total cost in dollars of hosting a birthday party at a skating rink to p the number of people attending If Alliersquos parents are willing to spend $300 for a party how many people can attend
25 Multi-Step The formula for the area of a triangle is A = 1 __ 2 bh in which b represents the length of thebase and h represents the height If a triangle has an area of 192 mm2 and the height is 12 mm what is the measure of the base
Lesson Performance TaskThe following table shows the average low temperatures in Fahrenheit for the city of Boston for several months during the year The formula F = 9 __ 5 C + 32 allows you to determine the temperature in Fahrenheit when given the temperature in Celsius
MonthTemperature in
FahrenheitTemperature in
Celsius
January 22deg
April 41deg
July 65deg
October 47deg
December 28deg
a Use the information given to determine the average low temperatures in Celsius
b Would it ever be possible for the temperature in Celsius to have a greater value than the temperature in Fahrenheit Explain why or why not
Module 2 72 Lesson 3
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
Name Class Date
Resource Locker
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oug
hton
Mif
flin
Har
cour
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lishi
ng
Com
pan
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mag
e cr
edit
s copy
Patr
ick
Lan
eSo
mos
Imag
esC
orb
is
Explore Creating Inequalities from Verbal DescriptionsAn inequality is a statement that compares two expressions that are not strictly equal by using one of the following inequality signs
Symbol Meaning
lt is less than
le is less than or equal to
gt is greater than
ge is greater than or equal to
ne is not equal to
You have probably seen a sign at an amusement park saying something like ldquoYou must be at least 48 inches tall to ride this riderdquo This statement could be written as h ge 48 in where h represents the height of a person allowed to ride
Nora is planning a birthday party for her little sister Colleen Norarsquos budget will allow her to spend no more than $50 for party supplies Eight children including Colleen will attend the party and Nora wants to determine how much she could spend on party favors for each child She will also purchase a cake for $10 Write an inequality that represents the situation and find possible solutions
A First let c represent the cost of a party favor for each child Write an expression for the total cost of the party as a function of c
c +
B Which inequality symbol should be used to represent the phrase ldquono more thanrdquo
C Write the inequality that represents Norarsquos budget goal
8c + 10 le
D Suppose Nora finds party favors that cost $4 each Use a value of 4 for c and check to see if this inequality is true
8 middot 4 + 10 le 50
le 50
Module 2 73 Lesson 4
24 Creating and Solving Inequalities
Essential Question How do you write and solve an inequality that represents a real-world situation
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany
Is the inequality true
Could Nora buy $6 party favors for all of her guests without going over budget
Reflect
1 Why does an inequality represent Norarsquos budget calculation better than an equation
2 The solution set of an inequality consists of all values that make the statement true Describe the whole dollar amounts that are in the solution set for this situation
Explain 1 Creating and Solving Inequalities Involving the Distributive Property
You may need to use the Distributive Property before you can solve an inequality
Distributive Property If a b and c are real numbers then a(b + c) = ab + ac
The inequality sign must be reversed when multiplying or dividing both sides of an inequality by a negative number
Example 1
A Trina is buying 12 shirts for the drama club She will choose a style for the blank shirts and then pay an additional charge of $275 for each shirt to have the club logo If Trina cannot spend more than $99 how much can she spend on each blank shirt Write and solve an inequality to find the possible cost of each blank shirt
Let s represent the cost of each blank shirt
Write an inequality to represent the situation 12(s + 275) le 99
Use the Distributive Property 12s + 33 le 99
Subtraction Property of Inequality 12s + 33 - 33 le 99 - 33
Simplify 12s le 66
Division Property of Inequality 12s ___ 12 le 66 __ 12
Simplify s le 55
Module 2 74 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
copy H
oug
hton
Mif
flin
Har
cour
t Pub
lishi
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Com
pan
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Check your answer
Since s le 55 check a smaller number 12(5 + 275) le 99
Trina can order blank shirts that cost $550 or less 93 le 99 true
B Sergio needs to buy gifts for 8 friends He wants to give the same gift to all his friends and he plans to have the gifts wrapped for an additional charge of $150 each If Sergio spends at least $70 he will receive free shipping on his order Write and solve an inequality to determine how much Sergio needs to spend on each gift in order to receive free shipping
Let g be the cost of one gift
Write an inequality to represent the situation ( g + ) ge 70
Use the Distributive Property g + ge 70
Subtraction Property of Inequality g + 12 - ge 70 -
Simplify 8g ge
Division Property of Inequality 8g _
ge 58 _
Simplify g ge
Check your answer
Since g ge 725 check a larger number 8(8 + 150) ge 70
Sergio must spend at least on each gift ge 70
Reflect
3 Discussion Why is the first step in solving the inequality to use the Distributive Property instead of working inside the parentheses
Your Turn
4 Zachary is planning to send a video game to each of his two brothers If he buys the same game for both brothers and pays $475 to ship each game how much can he spend on each game without spending more than $100 Write and solve an inequality for this situation
Solve each inequality
5 4 _ 3 (6x + 9) lt 4 6 -2 ( 1 _ 4 x + 2 ) ge 5
Module 2 75 Lesson 4
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Explain 2 Creating and Solving Inequalities with Variables on Both Sides
Some inequalities have variable terms on both sides of the inequality symbol You can solve these inequalities the same way you solved equations with variables on both sides Use the properties of inequality to collect all the variable terms on one side and all the constant terms on the other side
Example 2
A The Daily Info charges a fee of $650 plus $80 per week to run an ad The Peoplersquos Paper charges $145 per week For how many weeks must an ad run for the total cost at the Daily Info to be less expensive than the cost at the Peoplersquos Paper Let w be the number of weeks the ad runs in the paper
Write an inequality to represent the situation 650 + 80w lt 145w
Subtraction Property of Inequality 650 + 80w - 80w lt 145w - 80w
Simplify 650 lt 65w
Division Property of Inequality 650 _ 65 lt 65w _ 65
Simplify 10 lt w
The total cost at the Daily Info is less than the cost at the Peoplersquos Paper if the ad runs for more than 10 weeks
B The Home Cleaning Company charges $312 to power-wash the siding of a house plus $12 for each window Power Clean charges $36 per window and the price includes power-washing the siding How many windows must a house have to make the total cost from The Home Cleaning Company less expensive than Power Clean Let w be the number of windows
Write an inequality to represent the situation +12w lt 36w
Subtraction Property of Inequality 312 + 12w - lt 36w -
Simplify 312 lt
Division Property of Inequality 312 _ lt 24w _
Simplify lt w
A house must have more than 13 windows for The Home Cleaning Company to be less expensive than Power Clean
Reflect
7 How would the final inequality change if you divided by ndash24 in the next to last step
Your Turn
8 The school band will sell pizzas to raise money for new uniforms The supplier charges $100 plus $4 per pizza The band members sell the pizzas for $7 each Write and solve an inequality to find how many pizzas the band members will have to sell to make a profit
Module 2 76 Lesson 4
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Elaborate
9 Which inequality symbol would you use to represent the following words or phrases Can you come up with more examples
a at most b farther than c younger than d up to
10 Discussion How are the steps to solving an inequality similar to those for solving an equation How are they different
11 Essential Question Check-In How can you write an inequality that represents a real-world situation
Write an inequality that represents the description and then solve
1 Max has more than 5 carrots (number of carrots Max has = c)
2 Brigitte is shorter than 5 feet (Brigittersquos height = h)
3 Twice a number (x) is less than 10 4 Six more than five times a number (x) is at least twenty-one
5 Dave has $15 to spend on an $8 book and two birthday cards (c) for his friends How much can he spend on each card if he buys the same card for each friend
6 Toni can carry up to 18 lb in her backpack Her lunch weighs 1 lb her gym clothes weigh 2 lb and her books (b) weigh 3 lb each How many books can she carry in her backpack
Evaluate Homework and Practice
bull Online Homeworkbull Hints and Helpbull Extra Practice
Module 2 77 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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Solve each inequality
7 3 (x - 2) gt -3 8 5 + 5 (x + 4) le 20 9 3 + 1 _ 2 (3 - x) lt -7
10 3 (x + 6) - 2 (x + 2) ge 10 11 5 (3 - x) -4 (2 - 3x) gt 2 12 1 _ 2 (4x - 2) - 2 _ 3 (6x + 9) le 4
13 x + 1 gt -5 (7 - 2x) 14 5 _ 3 (6x + 3) le 2x - 7
15 2x le - 2 __ 3 (4x + 4) 16 1 __ 2 (-2x - 10) gt 3 (4 - 6x)
17 -5 - 3x ge 2 (10 + 2x) + 3 18 -3 (9x + 20) ge 15x - 20
19 8 ( 1 _ 4 x - 3) + 24 lt 4 ( x + 5 ) 20 6x - 2 (x + 2) gt 2 - 3 (x + 3)
Module 2 78 Lesson 4
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21 Physics A crane cable can support a maximum load of 15000 kg If a bucket has a mass of 2000 kg and gravel has a mass of 1500 kg for every cubic meter how many cubic meters of gravel (g) can be safely lifted by the crane
22 Find the solution set of each inequality below and then determine which inequalities have the same solution set as 1 _ 3 ( -5x - 3 ) lt 14
a 1 _ 3 (5x + 3) gt -14 b 2 _ 5 (10x + 20) gt 44
c - 2 _ 5 (10x + 20) lt -44 d - 1 _ 3 (5x + 3) lt 14
e 2 _ 5 (10x - 20) gt -44 f 1 _ 3 (5x + 3) lt -14
HOT Focus on Higher Order Thinking
23 Explain the Error Sven is trying to find the maximum amount of time he can spend practicing the five scales of piano music he is supposed to be working on He has 60 minutes to practice piano and would like to spend at least 35 minutes playing songs instead of practicing scales So Sven sets up the following inequality where t is the number of minutes he spends on each scale and solves it
60 - 5t le 35-5t le -25
t ge 5
Sven has concluded that he should spend 5 minutes or more on each scale Is this correct If not what mistake did he make Then solve for the correct answer
Module 2 79 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
24 Critical Thinking Anika wants to determine the maximum number of tulip bulbs (t) she can purchase if each bulb costs $150 She will also need to purchase separate pots for each bulb at $125 each and a bag of potting soil for $1000 Set up an inequality to determine how many tulip bulbs Anika can purchase without spending more than $2000 and solve it Can Anika buy exactly enough bulbs and pots to spend the full $2000 Explain Can you think of a better inequality to describe the answer
25 Geometry The area of the triangle shown is no more than 10 square inches
a Write an inequality that can be used to find x
b Solve the inequality from part a c What is the maximum height of the triangle
Lesson Performance TaskWhen planning an airplane route the trip planner must be careful to consider the range the aircraft can travel and the availability of airports to stop and refuel
A large commercial jet airplane burns approximately 5 gallons of fuel per mile flown plus about 8500 gallons of fuel per trip to reach cruising altitude With a useable fuel capacity of 50000 gallons (there is additional fuel reserved for emergencies) describe the acceptable distance for which an airline could establish a non-stop flight
For flights originating from Chicago determine which cities could be safely reached by a non-stop flight
City Distance from Chicago (miles)
Bangalore India 8530
Jakarta Indonesia 9810
Johannesburg South Africa 8680
Moscow Russia 4970
Paris France 4130
Perth Australia 10970
Tokyo Japan 6300
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eva O
lesiaShutterstock
(2x - 3) in
4 in
Module 2 80 Lesson 4
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Name Class Date
Resource Locker
Explore Truth Tables and Compound StatementsA compound statement is formed by combining two or more simple statements A compound statement can be true or false A compound statement involving AND is true when both simple statements are true A compound statement involving OR is true when either one simple statement or both are true
A Complete the truth table
P QP
True or FalseQ
True or FalseP AND Q
True or False
A dog is a mammal Red is a color
A dog is a mammal Red is not a color
A dog is a fish Red is a color
A dog is a fish Red is not a color
B P AND Q is true when
C Complete the truth table
P QP
True or FalseQ
True or FalseP OR Q
True or False
1 is an odd number 2 is an even number
1 is an odd number 2 is an odd number
1 is an even number 2 is an even number
1 is an even number 2 is an odd number
D P OR Q is true when
Reflect
1 Give two simple statements P and Q for which P AND Q is false and P OR Q is true
Module 2 81 Lesson 5
25 Creating and Solving Compound Inequalities
Essential Question How can you solve a compound inequality and graph the solution set
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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Explain 1 Solving Compound Inequalities Involving ANDCombining two or more simple inequalities forms a compound inequality The graph of a compound inequality involving AND is the intersection or the overlapping region of the simple inequality graphs
Compound Inequalities AND
Words Algebra Graph
All real numbers greater than 2AND less than 6
x gt 2 AND x lt 62 lt x lt 6
All real numbers greater than or equal to 2 AND less than or equal to 6
x ge 2 AND x le 62 le x le 6
Example 1 Solve each compound inequality and graph the solutions
A 4 le x + 2 le 8
4 le x + 2 AND x + 2 le 8 Write the compound inequality using AND
4 - 2 le x + 2 - 2 x + 2 - 2 le 8 - 2 Subtract 2 from both sides of each simple inequality
2 le x x le 6 Simplify
Graph 2 le x
Graph x le 6
Graph the intersection by finding where the two graphs overlap
B -5 le 2x + 3 lt 9
-5 - le 2x + 3 - lt 9 - Subtract from each part of the inequality
le 2x lt Simplify
-8 _ le 2x _ lt 6 _ Divide each part of the inequality by
le x lt Simplify
Graph -4 le x
Graph x lt 3
Graph the intersection by finding where the two graphs overlap -1 0 1 2 3 4 5-5-4 -3 -2
0 2 4 6 8 10 12-8-6-4 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 82 Lesson 5
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Reflect
2 Discussion Explain why 2 le x le 6 can be considered the short method for writing the AND compound inequality x ge 2 AND x le 6
YourTurn
Solve each compound inequality and graph the solutions
3 -2 lt x - 3 lt 5
4 -10 lt 3x + 2 le 8
Explain 2 Solving Compound Inequalities Involving ORThe graph of a compound inequality involving OR is the union or the combined region of the simple inequality graphs
Compound Inequalities OR
Words Algebra Graph
All real numbers less than 2OR greater than 6
x lt 2 OR x gt 6
All real numbers less than or equal to 2OR greater than or equal to 6
x le 2 OR x ge 6
-1 0 1 2 3 4 5-5-4 -3 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 83 Lesson 5
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oug
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pany
Example 2 Solve each compound inequality and graph the solutions
A -4 + x gt 1 OR -4 + x lt -3
-4 + x gt 1 OR -4 + x lt -3 Write the compound inequality using OR
-4 + 4 + x gt 1 + 4 -4 + 4 + x lt -3 + 4 Add 4 to both sides of each simple inequality
x gt 5 x lt 1 Simplify
Graph x gt 5
Graph x lt 1
Graph the union by combining the graphs
B 2x le 6 OR 3x gt 12
2x le 6 OR 3x gt 12 Write the compound inequality using OR
2x _ le 6 _ OR 3x _ gt 12 _ Divide the first simple inequality by
x le OR x gt
Graph x le 3
Graph x gt 4
Graph the union by combining the graphs
Reflect
5 Critical Thinking What kind of compound inequality has no solution
Divide the second simple inequality by
Simplify
0 1 2 3 4 5 6-4 -3 -2 -1
-0 1 2 3 4 5 6-4 -3 -2 -1
Module 2 84 Lesson 5
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oug
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Your Turn
Solve each compound inequality and graph the solutions
6 x - 5 ge -2 OR x -5 le -6
7 4x -1 lt 15 OR 8x ge 48
Explain 3 Creating Compound Inequalities From GraphsGiven a number line graph with a solution set graphed you can create a compound inequality to fit the graph
Example 3 Write the compound inequality shown by each graph
A
The shaded portion of the graph is not between two values so the compound inequality involves OR
On the left the graph shows an arrow pointing left from -1 and a solid circle so use le
The inequality is x le -1
On the right the graph shows an arrow pointing right from 7 and a solid circle so use ge
The inequality is x ge 7
The compound inequality is x le -1 OR x ge 7
B
The graph is shaded between the values and so the compound inequality involves AND
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The compound inequality is
-1 0 1 2 3 4 5-5-4 -3 -2
4 5 6 7 8 9 100 1 2 3
2 3 4 5 6 7 8-2 -1 0 1
10 2 3 4 5 6 7 8 9-1
Module 2 85 Lesson 5
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oug
hton Mifflin H
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pany
Reflect
8 What is a short method to write the compound inequality x ge 0 AND x lt 6
Your Turn
Write the compound inequality shown by each graph
9
10
Explain 4 Expressing Acceptable Levels with Compound Inequalities
You can express quality-controls levels in real-world problems using compound inequalities
Example 4 Write a compound inequality to represent the indicated quality-control level and graph the solutions
A The recommended pH level for swimming pool water is between 72 and 76 inclusive
Let p be the pH level of swimming pool water
72 is less than or equal to pH level is less than or equal to 76
72 le p le 76
The compound inequality is 72 le p le 76
Graph the solutions
0-10 -8-9 -7-6 -5-4 -3 -2 -1
71 72 73 74 75 76 77 78 79 8070
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 86 Lesson 5
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oug
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B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
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oug
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pany
bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
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oug
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Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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age C
redits copy
Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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Mif
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Har
cour
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Com
pan
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mag
e C
red
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copy
bik
erid
erlo
nd
onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
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24 Match each statement with the algebraic expression that models it
A the price of a winter coat and a 20 discount x + 002x = 102x
B the base salary of an employee and a 2 salary increase x - 020x = 080x
C the cost of groceries and a 2 discount with coupons x + 020x = 120x
D the number of students attending school last year and a 20 increase from last year x - 002x = 098x
HOT Focus on Higher Order Thinking
25 Critique Reasoning A student is given the rectangle and the square shown The student states that the two figures have the same perimeter Is the student correct Explain your reasoning
26 Multi-Step Yon buys tickets to a concert for himself and a friend There is a tax of 6 on the price of the tickets and an additional booking fee of $20 for the transaction Write an algebraic expression to represent the price per person Simplify the expression if possible
x + 2
x + 2x
x + 4
Module 2 52 Lesson 1
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27 Persevere in Problem Solving Jerry is planting white daisies and red tulips in his garden and he wants to choose a pattern in which the tulips surround the daisies He uses tiles to generate patterns starting with two rows of three daisies He surrounds these daisies with a border of tulips The design continues as shown
a Jerry writes the expression 8(b - 1) + 10 for the number of tulips in each border wherein b is the border number and b ge 1 Explain why Jerryrsquos expression is correct
b Elaine wants to start with two rows of four daisies Her reasoning is that Jerry started with two rows of three daisies and his expression was 8(b - 1) + 10 so if she starts with two rows of four daisies her expression will be 10(b - 1) + 10 Is Elainersquos statement correct Explain
Border 1 Border 2 Border 3
Module 2 53 Lesson 1
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
Lesson Performance Task
Becky and Michele are both shopping for a new car at two different dealerships Dealership A is offering $500 cash back on any purchase while Dealership B is offering $1000 cash back The tax rate is 5 at Dealership A but 8 at Dealership B Becky wants to buy a car that is $15000 and Michele is planning to buy a car that costs $20000 Use algebraic expressions to help you answer the following questions
a At which dealership will Becky get the better deal How much does she save
b At which dealership will Michele get the better deal How much does she save
c What generalization can you make that would help any shopper know which dealership has the better deal [Hint At what price point would the two deals be equal]
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Tom G
rillC
orbis
Module 2 54 Lesson 1
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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Name Class Date
Resource Locker
Explore Creating Equations from Verbal Descriptions
You can use what you know about writing algebraic expressions to write an equation that represents a real-world situation
Suppose Cory and his friend Walter go to a movie Each of their tickets costs the same amount and they share a frozen yogurt that costs $550 The total amount they spend is $1990 How can you write an equation that describes the situation
A Identify the important information
The word tells you that the relationship describes an equation
The word total tells you that the operation involved in the relationship is
What numerical information do you have
What is the unknown quantity
B Write a verbal description
Choose a name for the variable In this case use c for
The verbal description is Twice the cost of plus the cost
of equals
C To write an equation write a numerical or expression for each quantity
and insert an equal sign in the appropriate place An equation is
Reflect
1 How can you use a verbal model to write an equation for the situation described
Module 2 55 Lesson 2
22 Creating and Solving EquationsEssential Question How do you use an equation to model and solve a real-world problem
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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age C
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igital
Vision
Getty Im
ages
2 Could you write a different equation to describe the situation Explain your reasoning
Explain 1 Creating and Solving Equations Involving the Distributive Property
When you create an equation to model a real-world problem your equation may involve the Distributive Property When you solve a real-world problem you should always check that your answer makes sense
Example 1 Write and solve an equation to solve each problem
A Aaron and Alice are bowling Alicersquos score is twice the difference of Aaronrsquos score and 5 The sum of their scores is 320 Find each studentrsquos bowling score
Write a verbal description of the basic situation
The sum of Aaronrsquos score and Alicersquos score is 320
Choose a variable for the unknown quantity and write an equation to model the detailed situation
Let a represent Aaronrsquos score Then 2 (a - 5) represents Alicersquos score
a + 2 (a - 5) = 320
Solve the equation for a
a + 2 (a - 5) = 320
a + 2a - 10 = 320 Distributive Property
3a - 10 = 320
3a - 10 + 10 = 320 + 10 Addition Property of Equality
3a = 330
3a _ 3 = 330 _ 3 Division Property of Equality
a = 110
So Aaronrsquos score is 110 and Alicersquos score is 2 (a - 5) = 2 (110 - 5) = 2 (105) = 210
Check that the answer makes sense
110 + 210 = 320 so the answer makes sense
B Mari Carlos and Amanda collect stamps Carlos has five more stamps than Mari and Amanda has three times as many stamps as Carlos Altogether they have 100 stamps Find the number of stamps each person has
Write a verbal description of the basic situation
Module 2 56 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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pan
y
Choose a variable for the unknown quantity and write an equation to model the detailed situation
Let s represent the number of stamps Mari has Then Carlos has stamps
and Amanda has stamps
s + + 3 ( ) =
Solve the equation for s
s + + 3 ( ) =
s + s + 5 + 3s + = Distributive Property
+ = Combine like terms
s = Subtraction Property of Equality
s = Division Property of Equality
So Mari has stamps Carlos has stamps and Amanda
has stamps
Check that the answer makes sense
+ + = the answer makes sense
=
Reflect
3 Would a fractional answer make sense in this situation
4 Discussion What might it mean if a check revealed that the answer to a real-world problem did not make sense
Module 2 57 Lesson 2
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Your Turn
Write and solve an equation to solve the problem
5 A rectangular garden is fenced on all sides with 256 feet of fencing The garden is 8 feet longer than it is wide Find the length and width of the garden
Explain 2 Creating and Solving Equations with Variables on Both Sides
In some equations variables appear on both sides You can use the properties of equality to collect the variable terms so that they all appear on one side of the equation
Example 2 Write and solve an equation to solve each problem
A Janine has job offers at two companies One company offers a starting salary of $28000 with a raise of $3000 each year The other company offers a starting salary of $36000 with a raise of $2000 each year In how many years would Janinersquos salary be the same with both companies What will the salary be
Write a verbal description of the basic situation
Let n represent the number of years it takes for the salaries to be equal
Base Salary A plus $3000 per year raise = Base Salary B + $2000 per year raise
28000 + 3000n = 36000 + 2000n
28000 + 3000n - 2000n = 36000 + 2000n - 2000n Subtraction Property of Equality
28000 + 1000n = 36000 Combine like terms
28000 + 1000n - 28000 = 36000 - 28000 Subtraction Property of Equality
1000n = 8000 1000n _ 1000 = 8000 _ 1000 Division Property of Equality
n = 8
28000 + 3000 (8) = 36000 + 2000 (8)
52000 = 52000
In 8 years the salaries offered by both companies will be $52000
(w + 8) feet
w feet
Module 2 58 Lesson 2
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Har
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pan
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B One moving company charges $800 plus $16 per hour Another moving company charges $720 plus $21 per hour At what number of hours will the charge by both companies be the same What is the charge
Write a verbal description of the basic situation Let t represent the number of hours that the move takes
Moving Charge A plus $16 per hour = Moving Charge B plus $21 per hour
800 + t = 720 + t
800 + t - t = 720 + t - t Subtraction Property of Equality
800 = 720 + t
800 - 720 = 720 + t - 720 Subtraction Property of Equality
= t
_ = t _
Division Property of Equality
t =
The charges are the same for a job that takes hours
Substitute the value 16 in the original equation
800 + 16t = 720 + 21t
800 + 16 ( ) = 720 + 21 ( ) 800 + = 720 +
=
After hours the moving charge for both companies will be
Reflect
6 Suppose you collected the variable terms on the other side of the equal sign to solve the equation Would that affect the solution
Module 2 59 Lesson 2
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oug
hton Mifflin H
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pany
Your Turn
Write and solve an equation to solve each problem7 Claire bought just enough fencing to enclose either a
rectangular garden or a triangular garden as shown The two gardens have the same perimeter How many feet of fencing did she buy
8 A veterinarian is changing the diets of two animals Simba and Cuddles Simba currently consumes 1200 Calories per day That number will increase by 100 Calories each day Cuddles currently consumes 3230 Calories a day That number will decrease by 190 Calories each day The patterns will continue until both animals are consuming the same number of Calories each day In how many days will that be How many Calories will each animal be consuming each day then
Explain 3 Constructing Equations from an Organized TableYou can use a table to organize information and see relationships
Example 3 Construct and solve an equation to solve the problem
Kim works 4 hours more each day than Jill does and Jack works 2 hours less each day than Jill does Over 2 days the number of hours Kim works is equal to the difference of 4 times the number of hours Jack works and the number of hours Jill works How many hours does each person work each day
Analyze Information
Identify the important information
bull Kim works hours more per day than Jill does
bull Jack works hours less per day than Jill does
Formulate a Plan
Make a table using the information given Let x be the number of hours Jill works in one day
Hours Worked Per Day Hours Worked Over 2 Days
Kim
Jill
Jack
Over 2 days the number of hours Kim works is equal to the difference of 4 times the number of hours Jack works and the number of hours Jill works
(3x - 3)(x - 3)
(2x - 1) (2x - 1)
2x
Module 2 60 Lesson 2
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pan
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Solve
2 (x + 4) = 4 2 (x - 2) - 2x
2 (x + 4) = (x - 2) - 2x Simplify
2x + = 8x - - 2x Distributive Property
2x + 8 = x - 16
2x + 8 + = 6x - 16 + Addition Property of Equality
2x + = 6x
2x + 24 - x = 6x - x Subtraction Property of Equality
24 = x
24 _ = x _ Division Property of Equality
= x
Jill works hours per day Kim works hours per day and Jack works
hours per day
Justify and Evaluate
Substitute x = 6 into the original equation
2 (6 + 4) = 4 2 (6 - 2) - 2x
2 ( ) = 8 ( ) - 2 ( ) =
Your Turn
Write and solve an equation to solve the problem
9 Lisa is 10 centimeters taller than her friend Ian Ian is 14 centimeters taller than Jim Every month their heights increase by 2 centimeters In 7 months the sum of Ianrsquos and Jimrsquos heights will be 170 centimeters more than Lisarsquos height How tall is Ian now
Height now Height after 7 months
Module 2 61 Lesson 2
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oug
hton Mifflin H
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pany
Elaborate
10 How can you use properties to solve equations with variables on both sides
11 How is a table helpful when constructing equations
12 When solving a real-world problem to find a personrsquos age would a negative solution make sense Explain
13 Essential Question Check-In How do you write an equation to represent a real-world situation
bull Online Homeworkbull Hints and Helpbull Extra Practice
Write an equation for each description
1 The sum of 14 and a number is equal to 17 2 A number increased by 10 is 114
3 The difference between a number and 12 is 20 4 Ten times the sum of half a number and 6 is 8
5 Two-thirds a number plus 4 is 7 6 Tanmayi wants to raise $175 for a school fundraiser She has raised $120 so far How much more does she need to reach her goal
7 Hector is visiting a cousin who lives 350 miles away He has driven 90 miles How many more miles does he need to drive to reach his cousinrsquos home
8 The length of a rectangle is twice its width The perimeter of the rectangle is 126 feet
Evaluate Homework and Practice
Module 2 62 Lesson 2
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Har
cour
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pan
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mag
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(t)copy
Pete
r K
imS
hutt
erst
ock
Write and solve an equation for each situation
9 In one baseball season Peter hit twice the difference of the number of home runs Alice hit and 6 Altogether they hit 18 home runs How many home runs did each player hit that season
10 The perimeter of a parallelogram is 72 meters The width of the parallelogram is 4 meters less than its length Find the length and the width of the parallelogram
11 One month Ruby worked 6 hours more than Isaac and Svetlana worked 4 times as many hours as Ruby Together they worked 126 hours Find the number of hours each person worked
12 In one day Annie traveled 5 times the sum of the number of hours Brian traveled and 2 Together they traveled 20 hours Find the number of hours each person traveled
13 Xian and his cousin Kai both collect stamps Xian has 56 stamps and Kai has 80 stamps The boys recently joined different stamp-collecting clubs Xianrsquos club will send him 12 new stamps per month Kairsquos club will send him 8 new stamps per month After how many months will Xian and Kai have the same number of stamps How many stamps will each have
14 Kenya plans to make a down payment plus monthly payments in order to buy a motorcycle At one dealer she would pay $2500 down and $150 each month At another dealer she would pay $3000 down and $125 each month After how many months would the total amount paid be the same for both dealers What would that amount be
ℓ meters
(ℓ - 4) meters
Module 2 63 Lesson 2
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oug
hton Mifflin H
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pany
15 Community Gym charges a $50 membership fee and a $55 monthly fee Workout Gym charges a $200 membership fee and a $45 monthly fee After how many months will the total amount of money paid to both gyms be the same What will the amount be
16 Tina is saving to buy a notebook computer She has two options The first option is to put $200 away initially and save $10 every month The second option is to put $100 away initially and save $30 every month After how many months would Tina save the same amount using either option How much would she save with either option
Use the table to answer each question
Starting Salary Yearly Salary Increase
Company A $24000 $3000
Company B $30000 $2400
Company C $36000 $2000
17 After how many years are the salaries offered by Company A and Company B the same
18 After how many years are the salaries offered by Company B and Company C the same
19 Paul started work at Company B ten years ago at the salary shown in the table At the same time Sharla started at Company C at the salary shown in the table Who earned more during the last year How much more
20 Georgersquos page contains twice as many typed words as Billrsquos page and Billrsquos page contains 50 fewer words than Charliersquos page If each person can type 60 words per minute after one minute the difference between twice the number of words on Billrsquos page and the number of words on Charliersquos page is 210 How many words did Billrsquos page contain initially Use a table to organize the information
Initial number of words
Total number of words after one minute
Module 2 64 Lesson 2
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oug
hton
Mif
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Har
cour
t Pub
lishi
ng
Com
pan
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21 Geometry Sammie bought just enough fencing to border either a rectangular plot or a square plot as shown The perimeters of the plots are the same How many meters of fencing did she buy
HOT Focus on Higher Order Thinking
22 Justify Reasoning Suppose you want to solve the equation 2a + b = 2a where a and b are nonzero real numbers Describe the solution to this equation Justify your description
23 Multi-step A patio in the shape of a rectangle is fenced on all sides with 134 feet of fencing The patio is 5 feet less wide than it is long
a What information can be used to solve the problem How can you find the information
b Describe how to find the area of the patio What is the area of the patio
24 Explain the Error Kevin and Brittany write an equation to represent the following relationship and both students solve their equation Who found the correct equation and solution Why is the other person incorrect
5 times the difference of a number and 20 is the same as half the sum of 4 more than 4 times a number
Kevin Brittany
5 (x - 20) = 1 _ 2 (4x + 4) 5 (20 + x) = 1 _ 2 (4x + 4)
5x - 100 = 2x + 2 100 - 5x = 2x + 2
3x - 100 = 2 100 - 7x = 2
3x = 102 -7x = -98
x = 34 x = 14
(3x + 2) meters
(x + 2) meters
(x + 2) meters
(x - 1) meters
ℓ feet
(ℓ - 5) feet
Module 2 65 Lesson 2
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oug
hton Mifflin H
arcourt Publishin
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pany
25 What If Alexa and Zack are solving the following problem
The number of miles on Car A is 50 miles more than the number of miles on Car B and the number of miles on Car B is 30 miles more than the number of miles on Car C All the cars travel 50 miles in 1 hour After 1 hour twice the number of miles on Car A is 70 miles less than 3 times the number of miles on Car C How many miles were there on Car B initially
Alexa assumes there are m miles on Car B Zack assumes there are m miles on Car C Will Zackrsquos answer be the same as Alexarsquos answer Explain
Lesson Performance Task
Stacy Oliver and Jivesh each plan to put a certain amount of money into their savings accounts that earn simple interest of 6 per year Stacy puts $550 more than Jivesh and Oliver puts in 2 times as much as Jivesh After a year the amount in Stacyrsquos account is 2 times the sum of $212 and the amount in Oliverrsquos account How much does each person initially put into his or her account Who had the most money in his or her account after a year Who had the least Explain
Zackrsquos Table Initial Miles
Miles after One Hour
Alexarsquos Table Initial Miles
Miles after One Hour
Amount in Account Initially Amount in Account after One Year
Module 2 66 Lesson 2
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oug
hton
Mif
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cour
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lishi
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Com
pan
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Name Class Date
Resource Locker
Explore Rearranging Mathematical FormulasLiteral Equations are equations that contain two or more variables There are many literal equations in the form of math science and engineering formulas These formulas may seem like they can only be solved for the variable that is isolated on one side of the formula By using inverse operations and the properties of equality a formula can be rearranged so any variable in the formula can be isolated It is no different than how equations are solved by using inverse operations and the properties of equality
How can you solve the equation 42 = 6x
A42 _ = 6x _ What is the reason for dividing
Why divide by
= x By rearranging the equation x was isolated and the solution was found
The mathematical formula for the volume of a rectangular prism B = Vh or V = ℓwh is a literal equation V represents volume ℓ represents length w represents width and h represents height Using inverse operations the formula can be rearranged to solve for any one of the variables that might be unknown Like solving for x a formula can be rearranged to isolate a variable
B In the formula V = ℓwh the variable h needs to be isolated
The operation of is used in the formula The inverse
operation should be used
to isolate
C V _____ = ℓwh _____
V _ =
The formula rearranged in this way can easily produce the height of the rectangular prism when the volume length and width are known
Reflect
1 Using the formula for a rectangular prism rewrite the formula to solve for ℓ
ℓw
h
Module 2 67 Lesson 3
23 Solving for a VariableEssential Question How do you rewrite formulas and literal equations
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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Photo
grap
hyAurora Ph
otosCorb
is
Explain 1 Rearranging Scientific FormulasUse inverse operations to isolate the unknown variable in a scientific formula
The formula for density is D = m __ V Lead has a very high density of 11340 kg m 3 Plastic foam has a very low density of 75 kg m 3 The formula for density can be rearranged to solve for V volume or m mass
Example 1
A A sinker on a fishing line is made of lead and has a volume of 0000015 m 3 What is the mass of the sinker
The density formula can be rearranged to isolate m the mass The values for volume and density can then be substituted into the formula to find the mass
D = m _ V
DV = ( m _ V ) V DV = m
(11340 kg m 3 ) (0000015 m 3 ) = m
017 kg asymp m
B The design for a life preserver requires 03 kilogram of plastic foam to provide proper buoyancy What is the volume of the plastic foam required
Rearrange the density formula to isolate V
D = m _ V
(D) V = m _ V
DV =
DV _ = m _
V =
Now substitute the given values
V = _
V = m 3
Your Turn
2 For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Determine the altitude in feet when t is -275 ∘F and g is 60 ∘F
Module 2 68 Lesson 3
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cour
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Explain 2 Rearranging Literal EquationsUsing inverse operations to rearrange literal equations can be applied to any formula The interest formula I = prt is another example of a literal equation In the formula I represents interest p the principal or the initial amount to which interest will be applied r the rate at which interest will be paid and t is the time in years
Example 2
A Find the number of years used in the calculation of a $1000 loan at an interest rate of 5 with interest totaling $600
Solve the formula for t
I = prt
I _ pr = prt
_ pr
I _ pr = t
Substitute the given values Since the interest rate is 5 r = 005$600 __
$1000 middot 005 = t
12 = t
So the length of time for the loan is 12 years
B Determine the interest rate for a $2000 loan that will be paid off in 4 years with interest totaling $640 In order to find the interest rate solve the formula for r
I = prt
I _ = prt _
_ = r
Now substitute the values and simplify
__
( ) ( ) = r
008 = r
So the interest rate is per year
Your Turn
3 The formula y = mx + b is the slope-intercept form of the equation of a line Solve the equation for m
Module 2 69 Lesson 3
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
copy H
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pany
bull Online Homeworkbull Hints and Helpbull Extra Practice
Solve for the indicated variable in each mathematical formula
1 C = 2πr for r 2 A = 1 __ 2 bh for b 3 y = mx + b for x
4 A = 1 __ 2 (a + b)h for h 5 V = πr2h for h 6 SA = 2πr2 + 2πrh for h
Solve for the indicated variable in each scientific formula
7 d = rt for t 8 PV = nRT for T
9 A = FV - OV _______ T for OV 10 C = Wtc _ 1000 for W
Evaluate Homework and Practice
Elaborate
4 Discussion What could be a reason for isolating a variable in a literal equation
5 Describe a situation in which a formula could be used more easily if it were rearranged Include the formula in your description
6 Essential Question Check-In How do you isolate a variable
Module 2 70 Lesson 3
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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hton
Mif
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cour
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pan
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mag
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copyO
cean
C
orb
is
Solve for the indicated variable in each literal equation
11 2p + 5r = q for p 12 -10 = xy + z for x 13 a __ b = c for b
14 h - 4 _ j = k for j 15 x __ 5 - g = a for x 16 5p + 9c = p for c
17 2 __ 5 (z + 1) = y for z 18 g (h + 2 __ 3 ) = 1 for h 19 a(n - 3) + 8 = bn for n
20 Which is a possible way to rewrite the equation y = 3x + 3b to solve for b
A b = y - 3x
_ 3 C b = y - 3
_____ 3x
B b = 3(y - 3x) D b = x(y - 3)
21 Sports To find a baseball pitcherrsquos earned run average (ERA) you can use the formula Ei = 9r in which E represents ERA i represents the number of innings pitched and r represents the number of earned runs allowed Solve the equation for E What is a pitcherrsquos ERA if he allows 5 earned runs in 18 innings pitched
22 Meteorology For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Solve the equation for a If the atmospheric temperature is -655 ∘F and the ground temperature is 57 ∘F what is the altitude
Module 2 71 Lesson 3
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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arcourt Publishin
g Com
pany bull Im
age C
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Rand
y D
uch
aineA
lamy
HOT Focus on Higher Order Thinking
23 Explain the Error A student was asked to use the formula for the perimeter of a rectangle P = 2ℓ + 2w to solve for ℓ The student came up with an answer P - 2w = 2ℓ What error did the student make Explain Then solve for ℓ
24 Multi-Step The formula c = 5p + 215 relates c the total cost in dollars of hosting a birthday party at a skating rink to p the number of people attending If Alliersquos parents are willing to spend $300 for a party how many people can attend
25 Multi-Step The formula for the area of a triangle is A = 1 __ 2 bh in which b represents the length of thebase and h represents the height If a triangle has an area of 192 mm2 and the height is 12 mm what is the measure of the base
Lesson Performance TaskThe following table shows the average low temperatures in Fahrenheit for the city of Boston for several months during the year The formula F = 9 __ 5 C + 32 allows you to determine the temperature in Fahrenheit when given the temperature in Celsius
MonthTemperature in
FahrenheitTemperature in
Celsius
January 22deg
April 41deg
July 65deg
October 47deg
December 28deg
a Use the information given to determine the average low temperatures in Celsius
b Would it ever be possible for the temperature in Celsius to have a greater value than the temperature in Fahrenheit Explain why or why not
Module 2 72 Lesson 3
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
Name Class Date
Resource Locker
copy H
oug
hton
Mif
flin
Har
cour
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lishi
ng
Com
pan
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mag
e cr
edit
s copy
Patr
ick
Lan
eSo
mos
Imag
esC
orb
is
Explore Creating Inequalities from Verbal DescriptionsAn inequality is a statement that compares two expressions that are not strictly equal by using one of the following inequality signs
Symbol Meaning
lt is less than
le is less than or equal to
gt is greater than
ge is greater than or equal to
ne is not equal to
You have probably seen a sign at an amusement park saying something like ldquoYou must be at least 48 inches tall to ride this riderdquo This statement could be written as h ge 48 in where h represents the height of a person allowed to ride
Nora is planning a birthday party for her little sister Colleen Norarsquos budget will allow her to spend no more than $50 for party supplies Eight children including Colleen will attend the party and Nora wants to determine how much she could spend on party favors for each child She will also purchase a cake for $10 Write an inequality that represents the situation and find possible solutions
A First let c represent the cost of a party favor for each child Write an expression for the total cost of the party as a function of c
c +
B Which inequality symbol should be used to represent the phrase ldquono more thanrdquo
C Write the inequality that represents Norarsquos budget goal
8c + 10 le
D Suppose Nora finds party favors that cost $4 each Use a value of 4 for c and check to see if this inequality is true
8 middot 4 + 10 le 50
le 50
Module 2 73 Lesson 4
24 Creating and Solving Inequalities
Essential Question How do you write and solve an inequality that represents a real-world situation
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
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pany
Is the inequality true
Could Nora buy $6 party favors for all of her guests without going over budget
Reflect
1 Why does an inequality represent Norarsquos budget calculation better than an equation
2 The solution set of an inequality consists of all values that make the statement true Describe the whole dollar amounts that are in the solution set for this situation
Explain 1 Creating and Solving Inequalities Involving the Distributive Property
You may need to use the Distributive Property before you can solve an inequality
Distributive Property If a b and c are real numbers then a(b + c) = ab + ac
The inequality sign must be reversed when multiplying or dividing both sides of an inequality by a negative number
Example 1
A Trina is buying 12 shirts for the drama club She will choose a style for the blank shirts and then pay an additional charge of $275 for each shirt to have the club logo If Trina cannot spend more than $99 how much can she spend on each blank shirt Write and solve an inequality to find the possible cost of each blank shirt
Let s represent the cost of each blank shirt
Write an inequality to represent the situation 12(s + 275) le 99
Use the Distributive Property 12s + 33 le 99
Subtraction Property of Inequality 12s + 33 - 33 le 99 - 33
Simplify 12s le 66
Division Property of Inequality 12s ___ 12 le 66 __ 12
Simplify s le 55
Module 2 74 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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oug
hton
Mif
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Har
cour
t Pub
lishi
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Com
pan
y
Check your answer
Since s le 55 check a smaller number 12(5 + 275) le 99
Trina can order blank shirts that cost $550 or less 93 le 99 true
B Sergio needs to buy gifts for 8 friends He wants to give the same gift to all his friends and he plans to have the gifts wrapped for an additional charge of $150 each If Sergio spends at least $70 he will receive free shipping on his order Write and solve an inequality to determine how much Sergio needs to spend on each gift in order to receive free shipping
Let g be the cost of one gift
Write an inequality to represent the situation ( g + ) ge 70
Use the Distributive Property g + ge 70
Subtraction Property of Inequality g + 12 - ge 70 -
Simplify 8g ge
Division Property of Inequality 8g _
ge 58 _
Simplify g ge
Check your answer
Since g ge 725 check a larger number 8(8 + 150) ge 70
Sergio must spend at least on each gift ge 70
Reflect
3 Discussion Why is the first step in solving the inequality to use the Distributive Property instead of working inside the parentheses
Your Turn
4 Zachary is planning to send a video game to each of his two brothers If he buys the same game for both brothers and pays $475 to ship each game how much can he spend on each game without spending more than $100 Write and solve an inequality for this situation
Solve each inequality
5 4 _ 3 (6x + 9) lt 4 6 -2 ( 1 _ 4 x + 2 ) ge 5
Module 2 75 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
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pany
Explain 2 Creating and Solving Inequalities with Variables on Both Sides
Some inequalities have variable terms on both sides of the inequality symbol You can solve these inequalities the same way you solved equations with variables on both sides Use the properties of inequality to collect all the variable terms on one side and all the constant terms on the other side
Example 2
A The Daily Info charges a fee of $650 plus $80 per week to run an ad The Peoplersquos Paper charges $145 per week For how many weeks must an ad run for the total cost at the Daily Info to be less expensive than the cost at the Peoplersquos Paper Let w be the number of weeks the ad runs in the paper
Write an inequality to represent the situation 650 + 80w lt 145w
Subtraction Property of Inequality 650 + 80w - 80w lt 145w - 80w
Simplify 650 lt 65w
Division Property of Inequality 650 _ 65 lt 65w _ 65
Simplify 10 lt w
The total cost at the Daily Info is less than the cost at the Peoplersquos Paper if the ad runs for more than 10 weeks
B The Home Cleaning Company charges $312 to power-wash the siding of a house plus $12 for each window Power Clean charges $36 per window and the price includes power-washing the siding How many windows must a house have to make the total cost from The Home Cleaning Company less expensive than Power Clean Let w be the number of windows
Write an inequality to represent the situation +12w lt 36w
Subtraction Property of Inequality 312 + 12w - lt 36w -
Simplify 312 lt
Division Property of Inequality 312 _ lt 24w _
Simplify lt w
A house must have more than 13 windows for The Home Cleaning Company to be less expensive than Power Clean
Reflect
7 How would the final inequality change if you divided by ndash24 in the next to last step
Your Turn
8 The school band will sell pizzas to raise money for new uniforms The supplier charges $100 plus $4 per pizza The band members sell the pizzas for $7 each Write and solve an inequality to find how many pizzas the band members will have to sell to make a profit
Module 2 76 Lesson 4
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Elaborate
9 Which inequality symbol would you use to represent the following words or phrases Can you come up with more examples
a at most b farther than c younger than d up to
10 Discussion How are the steps to solving an inequality similar to those for solving an equation How are they different
11 Essential Question Check-In How can you write an inequality that represents a real-world situation
Write an inequality that represents the description and then solve
1 Max has more than 5 carrots (number of carrots Max has = c)
2 Brigitte is shorter than 5 feet (Brigittersquos height = h)
3 Twice a number (x) is less than 10 4 Six more than five times a number (x) is at least twenty-one
5 Dave has $15 to spend on an $8 book and two birthday cards (c) for his friends How much can he spend on each card if he buys the same card for each friend
6 Toni can carry up to 18 lb in her backpack Her lunch weighs 1 lb her gym clothes weigh 2 lb and her books (b) weigh 3 lb each How many books can she carry in her backpack
Evaluate Homework and Practice
bull Online Homeworkbull Hints and Helpbull Extra Practice
Module 2 77 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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pany
Solve each inequality
7 3 (x - 2) gt -3 8 5 + 5 (x + 4) le 20 9 3 + 1 _ 2 (3 - x) lt -7
10 3 (x + 6) - 2 (x + 2) ge 10 11 5 (3 - x) -4 (2 - 3x) gt 2 12 1 _ 2 (4x - 2) - 2 _ 3 (6x + 9) le 4
13 x + 1 gt -5 (7 - 2x) 14 5 _ 3 (6x + 3) le 2x - 7
15 2x le - 2 __ 3 (4x + 4) 16 1 __ 2 (-2x - 10) gt 3 (4 - 6x)
17 -5 - 3x ge 2 (10 + 2x) + 3 18 -3 (9x + 20) ge 15x - 20
19 8 ( 1 _ 4 x - 3) + 24 lt 4 ( x + 5 ) 20 6x - 2 (x + 2) gt 2 - 3 (x + 3)
Module 2 78 Lesson 4
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21 Physics A crane cable can support a maximum load of 15000 kg If a bucket has a mass of 2000 kg and gravel has a mass of 1500 kg for every cubic meter how many cubic meters of gravel (g) can be safely lifted by the crane
22 Find the solution set of each inequality below and then determine which inequalities have the same solution set as 1 _ 3 ( -5x - 3 ) lt 14
a 1 _ 3 (5x + 3) gt -14 b 2 _ 5 (10x + 20) gt 44
c - 2 _ 5 (10x + 20) lt -44 d - 1 _ 3 (5x + 3) lt 14
e 2 _ 5 (10x - 20) gt -44 f 1 _ 3 (5x + 3) lt -14
HOT Focus on Higher Order Thinking
23 Explain the Error Sven is trying to find the maximum amount of time he can spend practicing the five scales of piano music he is supposed to be working on He has 60 minutes to practice piano and would like to spend at least 35 minutes playing songs instead of practicing scales So Sven sets up the following inequality where t is the number of minutes he spends on each scale and solves it
60 - 5t le 35-5t le -25
t ge 5
Sven has concluded that he should spend 5 minutes or more on each scale Is this correct If not what mistake did he make Then solve for the correct answer
Module 2 79 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
24 Critical Thinking Anika wants to determine the maximum number of tulip bulbs (t) she can purchase if each bulb costs $150 She will also need to purchase separate pots for each bulb at $125 each and a bag of potting soil for $1000 Set up an inequality to determine how many tulip bulbs Anika can purchase without spending more than $2000 and solve it Can Anika buy exactly enough bulbs and pots to spend the full $2000 Explain Can you think of a better inequality to describe the answer
25 Geometry The area of the triangle shown is no more than 10 square inches
a Write an inequality that can be used to find x
b Solve the inequality from part a c What is the maximum height of the triangle
Lesson Performance TaskWhen planning an airplane route the trip planner must be careful to consider the range the aircraft can travel and the availability of airports to stop and refuel
A large commercial jet airplane burns approximately 5 gallons of fuel per mile flown plus about 8500 gallons of fuel per trip to reach cruising altitude With a useable fuel capacity of 50000 gallons (there is additional fuel reserved for emergencies) describe the acceptable distance for which an airline could establish a non-stop flight
For flights originating from Chicago determine which cities could be safely reached by a non-stop flight
City Distance from Chicago (miles)
Bangalore India 8530
Jakarta Indonesia 9810
Johannesburg South Africa 8680
Moscow Russia 4970
Paris France 4130
Perth Australia 10970
Tokyo Japan 6300
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oug
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eva O
lesiaShutterstock
(2x - 3) in
4 in
Module 2 80 Lesson 4
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Name Class Date
Resource Locker
Explore Truth Tables and Compound StatementsA compound statement is formed by combining two or more simple statements A compound statement can be true or false A compound statement involving AND is true when both simple statements are true A compound statement involving OR is true when either one simple statement or both are true
A Complete the truth table
P QP
True or FalseQ
True or FalseP AND Q
True or False
A dog is a mammal Red is a color
A dog is a mammal Red is not a color
A dog is a fish Red is a color
A dog is a fish Red is not a color
B P AND Q is true when
C Complete the truth table
P QP
True or FalseQ
True or FalseP OR Q
True or False
1 is an odd number 2 is an even number
1 is an odd number 2 is an odd number
1 is an even number 2 is an even number
1 is an even number 2 is an odd number
D P OR Q is true when
Reflect
1 Give two simple statements P and Q for which P AND Q is false and P OR Q is true
Module 2 81 Lesson 5
25 Creating and Solving Compound Inequalities
Essential Question How can you solve a compound inequality and graph the solution set
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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Explain 1 Solving Compound Inequalities Involving ANDCombining two or more simple inequalities forms a compound inequality The graph of a compound inequality involving AND is the intersection or the overlapping region of the simple inequality graphs
Compound Inequalities AND
Words Algebra Graph
All real numbers greater than 2AND less than 6
x gt 2 AND x lt 62 lt x lt 6
All real numbers greater than or equal to 2 AND less than or equal to 6
x ge 2 AND x le 62 le x le 6
Example 1 Solve each compound inequality and graph the solutions
A 4 le x + 2 le 8
4 le x + 2 AND x + 2 le 8 Write the compound inequality using AND
4 - 2 le x + 2 - 2 x + 2 - 2 le 8 - 2 Subtract 2 from both sides of each simple inequality
2 le x x le 6 Simplify
Graph 2 le x
Graph x le 6
Graph the intersection by finding where the two graphs overlap
B -5 le 2x + 3 lt 9
-5 - le 2x + 3 - lt 9 - Subtract from each part of the inequality
le 2x lt Simplify
-8 _ le 2x _ lt 6 _ Divide each part of the inequality by
le x lt Simplify
Graph -4 le x
Graph x lt 3
Graph the intersection by finding where the two graphs overlap -1 0 1 2 3 4 5-5-4 -3 -2
0 2 4 6 8 10 12-8-6-4 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 82 Lesson 5
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Reflect
2 Discussion Explain why 2 le x le 6 can be considered the short method for writing the AND compound inequality x ge 2 AND x le 6
YourTurn
Solve each compound inequality and graph the solutions
3 -2 lt x - 3 lt 5
4 -10 lt 3x + 2 le 8
Explain 2 Solving Compound Inequalities Involving ORThe graph of a compound inequality involving OR is the union or the combined region of the simple inequality graphs
Compound Inequalities OR
Words Algebra Graph
All real numbers less than 2OR greater than 6
x lt 2 OR x gt 6
All real numbers less than or equal to 2OR greater than or equal to 6
x le 2 OR x ge 6
-1 0 1 2 3 4 5-5-4 -3 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 83 Lesson 5
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oug
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Example 2 Solve each compound inequality and graph the solutions
A -4 + x gt 1 OR -4 + x lt -3
-4 + x gt 1 OR -4 + x lt -3 Write the compound inequality using OR
-4 + 4 + x gt 1 + 4 -4 + 4 + x lt -3 + 4 Add 4 to both sides of each simple inequality
x gt 5 x lt 1 Simplify
Graph x gt 5
Graph x lt 1
Graph the union by combining the graphs
B 2x le 6 OR 3x gt 12
2x le 6 OR 3x gt 12 Write the compound inequality using OR
2x _ le 6 _ OR 3x _ gt 12 _ Divide the first simple inequality by
x le OR x gt
Graph x le 3
Graph x gt 4
Graph the union by combining the graphs
Reflect
5 Critical Thinking What kind of compound inequality has no solution
Divide the second simple inequality by
Simplify
0 1 2 3 4 5 6-4 -3 -2 -1
-0 1 2 3 4 5 6-4 -3 -2 -1
Module 2 84 Lesson 5
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oug
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Your Turn
Solve each compound inequality and graph the solutions
6 x - 5 ge -2 OR x -5 le -6
7 4x -1 lt 15 OR 8x ge 48
Explain 3 Creating Compound Inequalities From GraphsGiven a number line graph with a solution set graphed you can create a compound inequality to fit the graph
Example 3 Write the compound inequality shown by each graph
A
The shaded portion of the graph is not between two values so the compound inequality involves OR
On the left the graph shows an arrow pointing left from -1 and a solid circle so use le
The inequality is x le -1
On the right the graph shows an arrow pointing right from 7 and a solid circle so use ge
The inequality is x ge 7
The compound inequality is x le -1 OR x ge 7
B
The graph is shaded between the values and so the compound inequality involves AND
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The compound inequality is
-1 0 1 2 3 4 5-5-4 -3 -2
4 5 6 7 8 9 100 1 2 3
2 3 4 5 6 7 8-2 -1 0 1
10 2 3 4 5 6 7 8 9-1
Module 2 85 Lesson 5
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oug
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pany
Reflect
8 What is a short method to write the compound inequality x ge 0 AND x lt 6
Your Turn
Write the compound inequality shown by each graph
9
10
Explain 4 Expressing Acceptable Levels with Compound Inequalities
You can express quality-controls levels in real-world problems using compound inequalities
Example 4 Write a compound inequality to represent the indicated quality-control level and graph the solutions
A The recommended pH level for swimming pool water is between 72 and 76 inclusive
Let p be the pH level of swimming pool water
72 is less than or equal to pH level is less than or equal to 76
72 le p le 76
The compound inequality is 72 le p le 76
Graph the solutions
0-10 -8-9 -7-6 -5-4 -3 -2 -1
71 72 73 74 75 76 77 78 79 8070
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 86 Lesson 5
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B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
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oug
hton Mifflin H
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pany
bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
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oug
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Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
arcourt Publishin
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pany bull Im
age C
redits copy
Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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Mif
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cour
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Com
pan
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mag
e C
red
its
copy
bik
erid
erlo
nd
onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
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27 Persevere in Problem Solving Jerry is planting white daisies and red tulips in his garden and he wants to choose a pattern in which the tulips surround the daisies He uses tiles to generate patterns starting with two rows of three daisies He surrounds these daisies with a border of tulips The design continues as shown
a Jerry writes the expression 8(b - 1) + 10 for the number of tulips in each border wherein b is the border number and b ge 1 Explain why Jerryrsquos expression is correct
b Elaine wants to start with two rows of four daisies Her reasoning is that Jerry started with two rows of three daisies and his expression was 8(b - 1) + 10 so if she starts with two rows of four daisies her expression will be 10(b - 1) + 10 Is Elainersquos statement correct Explain
Border 1 Border 2 Border 3
Module 2 53 Lesson 1
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
Lesson Performance Task
Becky and Michele are both shopping for a new car at two different dealerships Dealership A is offering $500 cash back on any purchase while Dealership B is offering $1000 cash back The tax rate is 5 at Dealership A but 8 at Dealership B Becky wants to buy a car that is $15000 and Michele is planning to buy a car that costs $20000 Use algebraic expressions to help you answer the following questions
a At which dealership will Becky get the better deal How much does she save
b At which dealership will Michele get the better deal How much does she save
c What generalization can you make that would help any shopper know which dealership has the better deal [Hint At what price point would the two deals be equal]
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oug
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age C
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Tom G
rillC
orbis
Module 2 54 Lesson 1
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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Mif
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cour
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Name Class Date
Resource Locker
Explore Creating Equations from Verbal Descriptions
You can use what you know about writing algebraic expressions to write an equation that represents a real-world situation
Suppose Cory and his friend Walter go to a movie Each of their tickets costs the same amount and they share a frozen yogurt that costs $550 The total amount they spend is $1990 How can you write an equation that describes the situation
A Identify the important information
The word tells you that the relationship describes an equation
The word total tells you that the operation involved in the relationship is
What numerical information do you have
What is the unknown quantity
B Write a verbal description
Choose a name for the variable In this case use c for
The verbal description is Twice the cost of plus the cost
of equals
C To write an equation write a numerical or expression for each quantity
and insert an equal sign in the appropriate place An equation is
Reflect
1 How can you use a verbal model to write an equation for the situation described
Module 2 55 Lesson 2
22 Creating and Solving EquationsEssential Question How do you use an equation to model and solve a real-world problem
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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igital
Vision
Getty Im
ages
2 Could you write a different equation to describe the situation Explain your reasoning
Explain 1 Creating and Solving Equations Involving the Distributive Property
When you create an equation to model a real-world problem your equation may involve the Distributive Property When you solve a real-world problem you should always check that your answer makes sense
Example 1 Write and solve an equation to solve each problem
A Aaron and Alice are bowling Alicersquos score is twice the difference of Aaronrsquos score and 5 The sum of their scores is 320 Find each studentrsquos bowling score
Write a verbal description of the basic situation
The sum of Aaronrsquos score and Alicersquos score is 320
Choose a variable for the unknown quantity and write an equation to model the detailed situation
Let a represent Aaronrsquos score Then 2 (a - 5) represents Alicersquos score
a + 2 (a - 5) = 320
Solve the equation for a
a + 2 (a - 5) = 320
a + 2a - 10 = 320 Distributive Property
3a - 10 = 320
3a - 10 + 10 = 320 + 10 Addition Property of Equality
3a = 330
3a _ 3 = 330 _ 3 Division Property of Equality
a = 110
So Aaronrsquos score is 110 and Alicersquos score is 2 (a - 5) = 2 (110 - 5) = 2 (105) = 210
Check that the answer makes sense
110 + 210 = 320 so the answer makes sense
B Mari Carlos and Amanda collect stamps Carlos has five more stamps than Mari and Amanda has three times as many stamps as Carlos Altogether they have 100 stamps Find the number of stamps each person has
Write a verbal description of the basic situation
Module 2 56 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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Choose a variable for the unknown quantity and write an equation to model the detailed situation
Let s represent the number of stamps Mari has Then Carlos has stamps
and Amanda has stamps
s + + 3 ( ) =
Solve the equation for s
s + + 3 ( ) =
s + s + 5 + 3s + = Distributive Property
+ = Combine like terms
s = Subtraction Property of Equality
s = Division Property of Equality
So Mari has stamps Carlos has stamps and Amanda
has stamps
Check that the answer makes sense
+ + = the answer makes sense
=
Reflect
3 Would a fractional answer make sense in this situation
4 Discussion What might it mean if a check revealed that the answer to a real-world problem did not make sense
Module 2 57 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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pany
Your Turn
Write and solve an equation to solve the problem
5 A rectangular garden is fenced on all sides with 256 feet of fencing The garden is 8 feet longer than it is wide Find the length and width of the garden
Explain 2 Creating and Solving Equations with Variables on Both Sides
In some equations variables appear on both sides You can use the properties of equality to collect the variable terms so that they all appear on one side of the equation
Example 2 Write and solve an equation to solve each problem
A Janine has job offers at two companies One company offers a starting salary of $28000 with a raise of $3000 each year The other company offers a starting salary of $36000 with a raise of $2000 each year In how many years would Janinersquos salary be the same with both companies What will the salary be
Write a verbal description of the basic situation
Let n represent the number of years it takes for the salaries to be equal
Base Salary A plus $3000 per year raise = Base Salary B + $2000 per year raise
28000 + 3000n = 36000 + 2000n
28000 + 3000n - 2000n = 36000 + 2000n - 2000n Subtraction Property of Equality
28000 + 1000n = 36000 Combine like terms
28000 + 1000n - 28000 = 36000 - 28000 Subtraction Property of Equality
1000n = 8000 1000n _ 1000 = 8000 _ 1000 Division Property of Equality
n = 8
28000 + 3000 (8) = 36000 + 2000 (8)
52000 = 52000
In 8 years the salaries offered by both companies will be $52000
(w + 8) feet
w feet
Module 2 58 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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pan
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B One moving company charges $800 plus $16 per hour Another moving company charges $720 plus $21 per hour At what number of hours will the charge by both companies be the same What is the charge
Write a verbal description of the basic situation Let t represent the number of hours that the move takes
Moving Charge A plus $16 per hour = Moving Charge B plus $21 per hour
800 + t = 720 + t
800 + t - t = 720 + t - t Subtraction Property of Equality
800 = 720 + t
800 - 720 = 720 + t - 720 Subtraction Property of Equality
= t
_ = t _
Division Property of Equality
t =
The charges are the same for a job that takes hours
Substitute the value 16 in the original equation
800 + 16t = 720 + 21t
800 + 16 ( ) = 720 + 21 ( ) 800 + = 720 +
=
After hours the moving charge for both companies will be
Reflect
6 Suppose you collected the variable terms on the other side of the equal sign to solve the equation Would that affect the solution
Module 2 59 Lesson 2
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pany
Your Turn
Write and solve an equation to solve each problem7 Claire bought just enough fencing to enclose either a
rectangular garden or a triangular garden as shown The two gardens have the same perimeter How many feet of fencing did she buy
8 A veterinarian is changing the diets of two animals Simba and Cuddles Simba currently consumes 1200 Calories per day That number will increase by 100 Calories each day Cuddles currently consumes 3230 Calories a day That number will decrease by 190 Calories each day The patterns will continue until both animals are consuming the same number of Calories each day In how many days will that be How many Calories will each animal be consuming each day then
Explain 3 Constructing Equations from an Organized TableYou can use a table to organize information and see relationships
Example 3 Construct and solve an equation to solve the problem
Kim works 4 hours more each day than Jill does and Jack works 2 hours less each day than Jill does Over 2 days the number of hours Kim works is equal to the difference of 4 times the number of hours Jack works and the number of hours Jill works How many hours does each person work each day
Analyze Information
Identify the important information
bull Kim works hours more per day than Jill does
bull Jack works hours less per day than Jill does
Formulate a Plan
Make a table using the information given Let x be the number of hours Jill works in one day
Hours Worked Per Day Hours Worked Over 2 Days
Kim
Jill
Jack
Over 2 days the number of hours Kim works is equal to the difference of 4 times the number of hours Jack works and the number of hours Jill works
(3x - 3)(x - 3)
(2x - 1) (2x - 1)
2x
Module 2 60 Lesson 2
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pan
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Solve
2 (x + 4) = 4 2 (x - 2) - 2x
2 (x + 4) = (x - 2) - 2x Simplify
2x + = 8x - - 2x Distributive Property
2x + 8 = x - 16
2x + 8 + = 6x - 16 + Addition Property of Equality
2x + = 6x
2x + 24 - x = 6x - x Subtraction Property of Equality
24 = x
24 _ = x _ Division Property of Equality
= x
Jill works hours per day Kim works hours per day and Jack works
hours per day
Justify and Evaluate
Substitute x = 6 into the original equation
2 (6 + 4) = 4 2 (6 - 2) - 2x
2 ( ) = 8 ( ) - 2 ( ) =
Your Turn
Write and solve an equation to solve the problem
9 Lisa is 10 centimeters taller than her friend Ian Ian is 14 centimeters taller than Jim Every month their heights increase by 2 centimeters In 7 months the sum of Ianrsquos and Jimrsquos heights will be 170 centimeters more than Lisarsquos height How tall is Ian now
Height now Height after 7 months
Module 2 61 Lesson 2
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arcourt Publishin
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pany
Elaborate
10 How can you use properties to solve equations with variables on both sides
11 How is a table helpful when constructing equations
12 When solving a real-world problem to find a personrsquos age would a negative solution make sense Explain
13 Essential Question Check-In How do you write an equation to represent a real-world situation
bull Online Homeworkbull Hints and Helpbull Extra Practice
Write an equation for each description
1 The sum of 14 and a number is equal to 17 2 A number increased by 10 is 114
3 The difference between a number and 12 is 20 4 Ten times the sum of half a number and 6 is 8
5 Two-thirds a number plus 4 is 7 6 Tanmayi wants to raise $175 for a school fundraiser She has raised $120 so far How much more does she need to reach her goal
7 Hector is visiting a cousin who lives 350 miles away He has driven 90 miles How many more miles does he need to drive to reach his cousinrsquos home
8 The length of a rectangle is twice its width The perimeter of the rectangle is 126 feet
Evaluate Homework and Practice
Module 2 62 Lesson 2
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(t)copy
Pete
r K
imS
hutt
erst
ock
Write and solve an equation for each situation
9 In one baseball season Peter hit twice the difference of the number of home runs Alice hit and 6 Altogether they hit 18 home runs How many home runs did each player hit that season
10 The perimeter of a parallelogram is 72 meters The width of the parallelogram is 4 meters less than its length Find the length and the width of the parallelogram
11 One month Ruby worked 6 hours more than Isaac and Svetlana worked 4 times as many hours as Ruby Together they worked 126 hours Find the number of hours each person worked
12 In one day Annie traveled 5 times the sum of the number of hours Brian traveled and 2 Together they traveled 20 hours Find the number of hours each person traveled
13 Xian and his cousin Kai both collect stamps Xian has 56 stamps and Kai has 80 stamps The boys recently joined different stamp-collecting clubs Xianrsquos club will send him 12 new stamps per month Kairsquos club will send him 8 new stamps per month After how many months will Xian and Kai have the same number of stamps How many stamps will each have
14 Kenya plans to make a down payment plus monthly payments in order to buy a motorcycle At one dealer she would pay $2500 down and $150 each month At another dealer she would pay $3000 down and $125 each month After how many months would the total amount paid be the same for both dealers What would that amount be
ℓ meters
(ℓ - 4) meters
Module 2 63 Lesson 2
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oug
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arcourt Publishin
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pany
15 Community Gym charges a $50 membership fee and a $55 monthly fee Workout Gym charges a $200 membership fee and a $45 monthly fee After how many months will the total amount of money paid to both gyms be the same What will the amount be
16 Tina is saving to buy a notebook computer She has two options The first option is to put $200 away initially and save $10 every month The second option is to put $100 away initially and save $30 every month After how many months would Tina save the same amount using either option How much would she save with either option
Use the table to answer each question
Starting Salary Yearly Salary Increase
Company A $24000 $3000
Company B $30000 $2400
Company C $36000 $2000
17 After how many years are the salaries offered by Company A and Company B the same
18 After how many years are the salaries offered by Company B and Company C the same
19 Paul started work at Company B ten years ago at the salary shown in the table At the same time Sharla started at Company C at the salary shown in the table Who earned more during the last year How much more
20 Georgersquos page contains twice as many typed words as Billrsquos page and Billrsquos page contains 50 fewer words than Charliersquos page If each person can type 60 words per minute after one minute the difference between twice the number of words on Billrsquos page and the number of words on Charliersquos page is 210 How many words did Billrsquos page contain initially Use a table to organize the information
Initial number of words
Total number of words after one minute
Module 2 64 Lesson 2
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oug
hton
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cour
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lishi
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Com
pan
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21 Geometry Sammie bought just enough fencing to border either a rectangular plot or a square plot as shown The perimeters of the plots are the same How many meters of fencing did she buy
HOT Focus on Higher Order Thinking
22 Justify Reasoning Suppose you want to solve the equation 2a + b = 2a where a and b are nonzero real numbers Describe the solution to this equation Justify your description
23 Multi-step A patio in the shape of a rectangle is fenced on all sides with 134 feet of fencing The patio is 5 feet less wide than it is long
a What information can be used to solve the problem How can you find the information
b Describe how to find the area of the patio What is the area of the patio
24 Explain the Error Kevin and Brittany write an equation to represent the following relationship and both students solve their equation Who found the correct equation and solution Why is the other person incorrect
5 times the difference of a number and 20 is the same as half the sum of 4 more than 4 times a number
Kevin Brittany
5 (x - 20) = 1 _ 2 (4x + 4) 5 (20 + x) = 1 _ 2 (4x + 4)
5x - 100 = 2x + 2 100 - 5x = 2x + 2
3x - 100 = 2 100 - 7x = 2
3x = 102 -7x = -98
x = 34 x = 14
(3x + 2) meters
(x + 2) meters
(x + 2) meters
(x - 1) meters
ℓ feet
(ℓ - 5) feet
Module 2 65 Lesson 2
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oug
hton Mifflin H
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pany
25 What If Alexa and Zack are solving the following problem
The number of miles on Car A is 50 miles more than the number of miles on Car B and the number of miles on Car B is 30 miles more than the number of miles on Car C All the cars travel 50 miles in 1 hour After 1 hour twice the number of miles on Car A is 70 miles less than 3 times the number of miles on Car C How many miles were there on Car B initially
Alexa assumes there are m miles on Car B Zack assumes there are m miles on Car C Will Zackrsquos answer be the same as Alexarsquos answer Explain
Lesson Performance Task
Stacy Oliver and Jivesh each plan to put a certain amount of money into their savings accounts that earn simple interest of 6 per year Stacy puts $550 more than Jivesh and Oliver puts in 2 times as much as Jivesh After a year the amount in Stacyrsquos account is 2 times the sum of $212 and the amount in Oliverrsquos account How much does each person initially put into his or her account Who had the most money in his or her account after a year Who had the least Explain
Zackrsquos Table Initial Miles
Miles after One Hour
Alexarsquos Table Initial Miles
Miles after One Hour
Amount in Account Initially Amount in Account after One Year
Module 2 66 Lesson 2
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oug
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pan
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Name Class Date
Resource Locker
Explore Rearranging Mathematical FormulasLiteral Equations are equations that contain two or more variables There are many literal equations in the form of math science and engineering formulas These formulas may seem like they can only be solved for the variable that is isolated on one side of the formula By using inverse operations and the properties of equality a formula can be rearranged so any variable in the formula can be isolated It is no different than how equations are solved by using inverse operations and the properties of equality
How can you solve the equation 42 = 6x
A42 _ = 6x _ What is the reason for dividing
Why divide by
= x By rearranging the equation x was isolated and the solution was found
The mathematical formula for the volume of a rectangular prism B = Vh or V = ℓwh is a literal equation V represents volume ℓ represents length w represents width and h represents height Using inverse operations the formula can be rearranged to solve for any one of the variables that might be unknown Like solving for x a formula can be rearranged to isolate a variable
B In the formula V = ℓwh the variable h needs to be isolated
The operation of is used in the formula The inverse
operation should be used
to isolate
C V _____ = ℓwh _____
V _ =
The formula rearranged in this way can easily produce the height of the rectangular prism when the volume length and width are known
Reflect
1 Using the formula for a rectangular prism rewrite the formula to solve for ℓ
ℓw
h
Module 2 67 Lesson 3
23 Solving for a VariableEssential Question How do you rewrite formulas and literal equations
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Photo
grap
hyAurora Ph
otosCorb
is
Explain 1 Rearranging Scientific FormulasUse inverse operations to isolate the unknown variable in a scientific formula
The formula for density is D = m __ V Lead has a very high density of 11340 kg m 3 Plastic foam has a very low density of 75 kg m 3 The formula for density can be rearranged to solve for V volume or m mass
Example 1
A A sinker on a fishing line is made of lead and has a volume of 0000015 m 3 What is the mass of the sinker
The density formula can be rearranged to isolate m the mass The values for volume and density can then be substituted into the formula to find the mass
D = m _ V
DV = ( m _ V ) V DV = m
(11340 kg m 3 ) (0000015 m 3 ) = m
017 kg asymp m
B The design for a life preserver requires 03 kilogram of plastic foam to provide proper buoyancy What is the volume of the plastic foam required
Rearrange the density formula to isolate V
D = m _ V
(D) V = m _ V
DV =
DV _ = m _
V =
Now substitute the given values
V = _
V = m 3
Your Turn
2 For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Determine the altitude in feet when t is -275 ∘F and g is 60 ∘F
Module 2 68 Lesson 3
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oug
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Mif
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cour
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Com
pan
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Explain 2 Rearranging Literal EquationsUsing inverse operations to rearrange literal equations can be applied to any formula The interest formula I = prt is another example of a literal equation In the formula I represents interest p the principal or the initial amount to which interest will be applied r the rate at which interest will be paid and t is the time in years
Example 2
A Find the number of years used in the calculation of a $1000 loan at an interest rate of 5 with interest totaling $600
Solve the formula for t
I = prt
I _ pr = prt
_ pr
I _ pr = t
Substitute the given values Since the interest rate is 5 r = 005$600 __
$1000 middot 005 = t
12 = t
So the length of time for the loan is 12 years
B Determine the interest rate for a $2000 loan that will be paid off in 4 years with interest totaling $640 In order to find the interest rate solve the formula for r
I = prt
I _ = prt _
_ = r
Now substitute the values and simplify
__
( ) ( ) = r
008 = r
So the interest rate is per year
Your Turn
3 The formula y = mx + b is the slope-intercept form of the equation of a line Solve the equation for m
Module 2 69 Lesson 3
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oug
hton Mifflin H
arcourt Publishin
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pany
bull Online Homeworkbull Hints and Helpbull Extra Practice
Solve for the indicated variable in each mathematical formula
1 C = 2πr for r 2 A = 1 __ 2 bh for b 3 y = mx + b for x
4 A = 1 __ 2 (a + b)h for h 5 V = πr2h for h 6 SA = 2πr2 + 2πrh for h
Solve for the indicated variable in each scientific formula
7 d = rt for t 8 PV = nRT for T
9 A = FV - OV _______ T for OV 10 C = Wtc _ 1000 for W
Evaluate Homework and Practice
Elaborate
4 Discussion What could be a reason for isolating a variable in a literal equation
5 Describe a situation in which a formula could be used more easily if it were rearranged Include the formula in your description
6 Essential Question Check-In How do you isolate a variable
Module 2 70 Lesson 3
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oug
hton
Mif
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Har
cour
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Com
pan
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mag
e C
red
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copyO
cean
C
orb
is
Solve for the indicated variable in each literal equation
11 2p + 5r = q for p 12 -10 = xy + z for x 13 a __ b = c for b
14 h - 4 _ j = k for j 15 x __ 5 - g = a for x 16 5p + 9c = p for c
17 2 __ 5 (z + 1) = y for z 18 g (h + 2 __ 3 ) = 1 for h 19 a(n - 3) + 8 = bn for n
20 Which is a possible way to rewrite the equation y = 3x + 3b to solve for b
A b = y - 3x
_ 3 C b = y - 3
_____ 3x
B b = 3(y - 3x) D b = x(y - 3)
21 Sports To find a baseball pitcherrsquos earned run average (ERA) you can use the formula Ei = 9r in which E represents ERA i represents the number of innings pitched and r represents the number of earned runs allowed Solve the equation for E What is a pitcherrsquos ERA if he allows 5 earned runs in 18 innings pitched
22 Meteorology For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Solve the equation for a If the atmospheric temperature is -655 ∘F and the ground temperature is 57 ∘F what is the altitude
Module 2 71 Lesson 3
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
arcourt Publishin
g Com
pany bull Im
age C
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Rand
y D
uch
aineA
lamy
HOT Focus on Higher Order Thinking
23 Explain the Error A student was asked to use the formula for the perimeter of a rectangle P = 2ℓ + 2w to solve for ℓ The student came up with an answer P - 2w = 2ℓ What error did the student make Explain Then solve for ℓ
24 Multi-Step The formula c = 5p + 215 relates c the total cost in dollars of hosting a birthday party at a skating rink to p the number of people attending If Alliersquos parents are willing to spend $300 for a party how many people can attend
25 Multi-Step The formula for the area of a triangle is A = 1 __ 2 bh in which b represents the length of thebase and h represents the height If a triangle has an area of 192 mm2 and the height is 12 mm what is the measure of the base
Lesson Performance TaskThe following table shows the average low temperatures in Fahrenheit for the city of Boston for several months during the year The formula F = 9 __ 5 C + 32 allows you to determine the temperature in Fahrenheit when given the temperature in Celsius
MonthTemperature in
FahrenheitTemperature in
Celsius
January 22deg
April 41deg
July 65deg
October 47deg
December 28deg
a Use the information given to determine the average low temperatures in Celsius
b Would it ever be possible for the temperature in Celsius to have a greater value than the temperature in Fahrenheit Explain why or why not
Module 2 72 Lesson 3
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
Name Class Date
Resource Locker
copy H
oug
hton
Mif
flin
Har
cour
t Pub
lishi
ng
Com
pan
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mag
e cr
edit
s copy
Patr
ick
Lan
eSo
mos
Imag
esC
orb
is
Explore Creating Inequalities from Verbal DescriptionsAn inequality is a statement that compares two expressions that are not strictly equal by using one of the following inequality signs
Symbol Meaning
lt is less than
le is less than or equal to
gt is greater than
ge is greater than or equal to
ne is not equal to
You have probably seen a sign at an amusement park saying something like ldquoYou must be at least 48 inches tall to ride this riderdquo This statement could be written as h ge 48 in where h represents the height of a person allowed to ride
Nora is planning a birthday party for her little sister Colleen Norarsquos budget will allow her to spend no more than $50 for party supplies Eight children including Colleen will attend the party and Nora wants to determine how much she could spend on party favors for each child She will also purchase a cake for $10 Write an inequality that represents the situation and find possible solutions
A First let c represent the cost of a party favor for each child Write an expression for the total cost of the party as a function of c
c +
B Which inequality symbol should be used to represent the phrase ldquono more thanrdquo
C Write the inequality that represents Norarsquos budget goal
8c + 10 le
D Suppose Nora finds party favors that cost $4 each Use a value of 4 for c and check to see if this inequality is true
8 middot 4 + 10 le 50
le 50
Module 2 73 Lesson 4
24 Creating and Solving Inequalities
Essential Question How do you write and solve an inequality that represents a real-world situation
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
arcourt Publishin
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pany
Is the inequality true
Could Nora buy $6 party favors for all of her guests without going over budget
Reflect
1 Why does an inequality represent Norarsquos budget calculation better than an equation
2 The solution set of an inequality consists of all values that make the statement true Describe the whole dollar amounts that are in the solution set for this situation
Explain 1 Creating and Solving Inequalities Involving the Distributive Property
You may need to use the Distributive Property before you can solve an inequality
Distributive Property If a b and c are real numbers then a(b + c) = ab + ac
The inequality sign must be reversed when multiplying or dividing both sides of an inequality by a negative number
Example 1
A Trina is buying 12 shirts for the drama club She will choose a style for the blank shirts and then pay an additional charge of $275 for each shirt to have the club logo If Trina cannot spend more than $99 how much can she spend on each blank shirt Write and solve an inequality to find the possible cost of each blank shirt
Let s represent the cost of each blank shirt
Write an inequality to represent the situation 12(s + 275) le 99
Use the Distributive Property 12s + 33 le 99
Subtraction Property of Inequality 12s + 33 - 33 le 99 - 33
Simplify 12s le 66
Division Property of Inequality 12s ___ 12 le 66 __ 12
Simplify s le 55
Module 2 74 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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oug
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Mif
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Har
cour
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lishi
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Com
pan
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Check your answer
Since s le 55 check a smaller number 12(5 + 275) le 99
Trina can order blank shirts that cost $550 or less 93 le 99 true
B Sergio needs to buy gifts for 8 friends He wants to give the same gift to all his friends and he plans to have the gifts wrapped for an additional charge of $150 each If Sergio spends at least $70 he will receive free shipping on his order Write and solve an inequality to determine how much Sergio needs to spend on each gift in order to receive free shipping
Let g be the cost of one gift
Write an inequality to represent the situation ( g + ) ge 70
Use the Distributive Property g + ge 70
Subtraction Property of Inequality g + 12 - ge 70 -
Simplify 8g ge
Division Property of Inequality 8g _
ge 58 _
Simplify g ge
Check your answer
Since g ge 725 check a larger number 8(8 + 150) ge 70
Sergio must spend at least on each gift ge 70
Reflect
3 Discussion Why is the first step in solving the inequality to use the Distributive Property instead of working inside the parentheses
Your Turn
4 Zachary is planning to send a video game to each of his two brothers If he buys the same game for both brothers and pays $475 to ship each game how much can he spend on each game without spending more than $100 Write and solve an inequality for this situation
Solve each inequality
5 4 _ 3 (6x + 9) lt 4 6 -2 ( 1 _ 4 x + 2 ) ge 5
Module 2 75 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
arcourt Publishin
g Com
pany
Explain 2 Creating and Solving Inequalities with Variables on Both Sides
Some inequalities have variable terms on both sides of the inequality symbol You can solve these inequalities the same way you solved equations with variables on both sides Use the properties of inequality to collect all the variable terms on one side and all the constant terms on the other side
Example 2
A The Daily Info charges a fee of $650 plus $80 per week to run an ad The Peoplersquos Paper charges $145 per week For how many weeks must an ad run for the total cost at the Daily Info to be less expensive than the cost at the Peoplersquos Paper Let w be the number of weeks the ad runs in the paper
Write an inequality to represent the situation 650 + 80w lt 145w
Subtraction Property of Inequality 650 + 80w - 80w lt 145w - 80w
Simplify 650 lt 65w
Division Property of Inequality 650 _ 65 lt 65w _ 65
Simplify 10 lt w
The total cost at the Daily Info is less than the cost at the Peoplersquos Paper if the ad runs for more than 10 weeks
B The Home Cleaning Company charges $312 to power-wash the siding of a house plus $12 for each window Power Clean charges $36 per window and the price includes power-washing the siding How many windows must a house have to make the total cost from The Home Cleaning Company less expensive than Power Clean Let w be the number of windows
Write an inequality to represent the situation +12w lt 36w
Subtraction Property of Inequality 312 + 12w - lt 36w -
Simplify 312 lt
Division Property of Inequality 312 _ lt 24w _
Simplify lt w
A house must have more than 13 windows for The Home Cleaning Company to be less expensive than Power Clean
Reflect
7 How would the final inequality change if you divided by ndash24 in the next to last step
Your Turn
8 The school band will sell pizzas to raise money for new uniforms The supplier charges $100 plus $4 per pizza The band members sell the pizzas for $7 each Write and solve an inequality to find how many pizzas the band members will have to sell to make a profit
Module 2 76 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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oug
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Mif
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Har
cour
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Com
pan
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Elaborate
9 Which inequality symbol would you use to represent the following words or phrases Can you come up with more examples
a at most b farther than c younger than d up to
10 Discussion How are the steps to solving an inequality similar to those for solving an equation How are they different
11 Essential Question Check-In How can you write an inequality that represents a real-world situation
Write an inequality that represents the description and then solve
1 Max has more than 5 carrots (number of carrots Max has = c)
2 Brigitte is shorter than 5 feet (Brigittersquos height = h)
3 Twice a number (x) is less than 10 4 Six more than five times a number (x) is at least twenty-one
5 Dave has $15 to spend on an $8 book and two birthday cards (c) for his friends How much can he spend on each card if he buys the same card for each friend
6 Toni can carry up to 18 lb in her backpack Her lunch weighs 1 lb her gym clothes weigh 2 lb and her books (b) weigh 3 lb each How many books can she carry in her backpack
Evaluate Homework and Practice
bull Online Homeworkbull Hints and Helpbull Extra Practice
Module 2 77 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany
Solve each inequality
7 3 (x - 2) gt -3 8 5 + 5 (x + 4) le 20 9 3 + 1 _ 2 (3 - x) lt -7
10 3 (x + 6) - 2 (x + 2) ge 10 11 5 (3 - x) -4 (2 - 3x) gt 2 12 1 _ 2 (4x - 2) - 2 _ 3 (6x + 9) le 4
13 x + 1 gt -5 (7 - 2x) 14 5 _ 3 (6x + 3) le 2x - 7
15 2x le - 2 __ 3 (4x + 4) 16 1 __ 2 (-2x - 10) gt 3 (4 - 6x)
17 -5 - 3x ge 2 (10 + 2x) + 3 18 -3 (9x + 20) ge 15x - 20
19 8 ( 1 _ 4 x - 3) + 24 lt 4 ( x + 5 ) 20 6x - 2 (x + 2) gt 2 - 3 (x + 3)
Module 2 78 Lesson 4
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oug
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Mif
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Har
cour
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pan
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21 Physics A crane cable can support a maximum load of 15000 kg If a bucket has a mass of 2000 kg and gravel has a mass of 1500 kg for every cubic meter how many cubic meters of gravel (g) can be safely lifted by the crane
22 Find the solution set of each inequality below and then determine which inequalities have the same solution set as 1 _ 3 ( -5x - 3 ) lt 14
a 1 _ 3 (5x + 3) gt -14 b 2 _ 5 (10x + 20) gt 44
c - 2 _ 5 (10x + 20) lt -44 d - 1 _ 3 (5x + 3) lt 14
e 2 _ 5 (10x - 20) gt -44 f 1 _ 3 (5x + 3) lt -14
HOT Focus on Higher Order Thinking
23 Explain the Error Sven is trying to find the maximum amount of time he can spend practicing the five scales of piano music he is supposed to be working on He has 60 minutes to practice piano and would like to spend at least 35 minutes playing songs instead of practicing scales So Sven sets up the following inequality where t is the number of minutes he spends on each scale and solves it
60 - 5t le 35-5t le -25
t ge 5
Sven has concluded that he should spend 5 minutes or more on each scale Is this correct If not what mistake did he make Then solve for the correct answer
Module 2 79 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
24 Critical Thinking Anika wants to determine the maximum number of tulip bulbs (t) she can purchase if each bulb costs $150 She will also need to purchase separate pots for each bulb at $125 each and a bag of potting soil for $1000 Set up an inequality to determine how many tulip bulbs Anika can purchase without spending more than $2000 and solve it Can Anika buy exactly enough bulbs and pots to spend the full $2000 Explain Can you think of a better inequality to describe the answer
25 Geometry The area of the triangle shown is no more than 10 square inches
a Write an inequality that can be used to find x
b Solve the inequality from part a c What is the maximum height of the triangle
Lesson Performance TaskWhen planning an airplane route the trip planner must be careful to consider the range the aircraft can travel and the availability of airports to stop and refuel
A large commercial jet airplane burns approximately 5 gallons of fuel per mile flown plus about 8500 gallons of fuel per trip to reach cruising altitude With a useable fuel capacity of 50000 gallons (there is additional fuel reserved for emergencies) describe the acceptable distance for which an airline could establish a non-stop flight
For flights originating from Chicago determine which cities could be safely reached by a non-stop flight
City Distance from Chicago (miles)
Bangalore India 8530
Jakarta Indonesia 9810
Johannesburg South Africa 8680
Moscow Russia 4970
Paris France 4130
Perth Australia 10970
Tokyo Japan 6300
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(2x - 3) in
4 in
Module 2 80 Lesson 4
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Name Class Date
Resource Locker
Explore Truth Tables and Compound StatementsA compound statement is formed by combining two or more simple statements A compound statement can be true or false A compound statement involving AND is true when both simple statements are true A compound statement involving OR is true when either one simple statement or both are true
A Complete the truth table
P QP
True or FalseQ
True or FalseP AND Q
True or False
A dog is a mammal Red is a color
A dog is a mammal Red is not a color
A dog is a fish Red is a color
A dog is a fish Red is not a color
B P AND Q is true when
C Complete the truth table
P QP
True or FalseQ
True or FalseP OR Q
True or False
1 is an odd number 2 is an even number
1 is an odd number 2 is an odd number
1 is an even number 2 is an even number
1 is an even number 2 is an odd number
D P OR Q is true when
Reflect
1 Give two simple statements P and Q for which P AND Q is false and P OR Q is true
Module 2 81 Lesson 5
25 Creating and Solving Compound Inequalities
Essential Question How can you solve a compound inequality and graph the solution set
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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Explain 1 Solving Compound Inequalities Involving ANDCombining two or more simple inequalities forms a compound inequality The graph of a compound inequality involving AND is the intersection or the overlapping region of the simple inequality graphs
Compound Inequalities AND
Words Algebra Graph
All real numbers greater than 2AND less than 6
x gt 2 AND x lt 62 lt x lt 6
All real numbers greater than or equal to 2 AND less than or equal to 6
x ge 2 AND x le 62 le x le 6
Example 1 Solve each compound inequality and graph the solutions
A 4 le x + 2 le 8
4 le x + 2 AND x + 2 le 8 Write the compound inequality using AND
4 - 2 le x + 2 - 2 x + 2 - 2 le 8 - 2 Subtract 2 from both sides of each simple inequality
2 le x x le 6 Simplify
Graph 2 le x
Graph x le 6
Graph the intersection by finding where the two graphs overlap
B -5 le 2x + 3 lt 9
-5 - le 2x + 3 - lt 9 - Subtract from each part of the inequality
le 2x lt Simplify
-8 _ le 2x _ lt 6 _ Divide each part of the inequality by
le x lt Simplify
Graph -4 le x
Graph x lt 3
Graph the intersection by finding where the two graphs overlap -1 0 1 2 3 4 5-5-4 -3 -2
0 2 4 6 8 10 12-8-6-4 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 82 Lesson 5
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Reflect
2 Discussion Explain why 2 le x le 6 can be considered the short method for writing the AND compound inequality x ge 2 AND x le 6
YourTurn
Solve each compound inequality and graph the solutions
3 -2 lt x - 3 lt 5
4 -10 lt 3x + 2 le 8
Explain 2 Solving Compound Inequalities Involving ORThe graph of a compound inequality involving OR is the union or the combined region of the simple inequality graphs
Compound Inequalities OR
Words Algebra Graph
All real numbers less than 2OR greater than 6
x lt 2 OR x gt 6
All real numbers less than or equal to 2OR greater than or equal to 6
x le 2 OR x ge 6
-1 0 1 2 3 4 5-5-4 -3 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 83 Lesson 5
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Example 2 Solve each compound inequality and graph the solutions
A -4 + x gt 1 OR -4 + x lt -3
-4 + x gt 1 OR -4 + x lt -3 Write the compound inequality using OR
-4 + 4 + x gt 1 + 4 -4 + 4 + x lt -3 + 4 Add 4 to both sides of each simple inequality
x gt 5 x lt 1 Simplify
Graph x gt 5
Graph x lt 1
Graph the union by combining the graphs
B 2x le 6 OR 3x gt 12
2x le 6 OR 3x gt 12 Write the compound inequality using OR
2x _ le 6 _ OR 3x _ gt 12 _ Divide the first simple inequality by
x le OR x gt
Graph x le 3
Graph x gt 4
Graph the union by combining the graphs
Reflect
5 Critical Thinking What kind of compound inequality has no solution
Divide the second simple inequality by
Simplify
0 1 2 3 4 5 6-4 -3 -2 -1
-0 1 2 3 4 5 6-4 -3 -2 -1
Module 2 84 Lesson 5
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Your Turn
Solve each compound inequality and graph the solutions
6 x - 5 ge -2 OR x -5 le -6
7 4x -1 lt 15 OR 8x ge 48
Explain 3 Creating Compound Inequalities From GraphsGiven a number line graph with a solution set graphed you can create a compound inequality to fit the graph
Example 3 Write the compound inequality shown by each graph
A
The shaded portion of the graph is not between two values so the compound inequality involves OR
On the left the graph shows an arrow pointing left from -1 and a solid circle so use le
The inequality is x le -1
On the right the graph shows an arrow pointing right from 7 and a solid circle so use ge
The inequality is x ge 7
The compound inequality is x le -1 OR x ge 7
B
The graph is shaded between the values and so the compound inequality involves AND
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The compound inequality is
-1 0 1 2 3 4 5-5-4 -3 -2
4 5 6 7 8 9 100 1 2 3
2 3 4 5 6 7 8-2 -1 0 1
10 2 3 4 5 6 7 8 9-1
Module 2 85 Lesson 5
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Reflect
8 What is a short method to write the compound inequality x ge 0 AND x lt 6
Your Turn
Write the compound inequality shown by each graph
9
10
Explain 4 Expressing Acceptable Levels with Compound Inequalities
You can express quality-controls levels in real-world problems using compound inequalities
Example 4 Write a compound inequality to represent the indicated quality-control level and graph the solutions
A The recommended pH level for swimming pool water is between 72 and 76 inclusive
Let p be the pH level of swimming pool water
72 is less than or equal to pH level is less than or equal to 76
72 le p le 76
The compound inequality is 72 le p le 76
Graph the solutions
0-10 -8-9 -7-6 -5-4 -3 -2 -1
71 72 73 74 75 76 77 78 79 8070
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 86 Lesson 5
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oug
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B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
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oug
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bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
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oug
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Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
arcourt Publishin
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age C
redits copy
Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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Mif
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cour
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Com
pan
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mag
e C
red
its
copy
bik
erid
erlo
nd
onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
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oug
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The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
Lesson Performance Task
Becky and Michele are both shopping for a new car at two different dealerships Dealership A is offering $500 cash back on any purchase while Dealership B is offering $1000 cash back The tax rate is 5 at Dealership A but 8 at Dealership B Becky wants to buy a car that is $15000 and Michele is planning to buy a car that costs $20000 Use algebraic expressions to help you answer the following questions
a At which dealership will Becky get the better deal How much does she save
b At which dealership will Michele get the better deal How much does she save
c What generalization can you make that would help any shopper know which dealership has the better deal [Hint At what price point would the two deals be equal]
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oug
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age C
redits copy
Tom G
rillC
orbis
Module 2 54 Lesson 1
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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Name Class Date
Resource Locker
Explore Creating Equations from Verbal Descriptions
You can use what you know about writing algebraic expressions to write an equation that represents a real-world situation
Suppose Cory and his friend Walter go to a movie Each of their tickets costs the same amount and they share a frozen yogurt that costs $550 The total amount they spend is $1990 How can you write an equation that describes the situation
A Identify the important information
The word tells you that the relationship describes an equation
The word total tells you that the operation involved in the relationship is
What numerical information do you have
What is the unknown quantity
B Write a verbal description
Choose a name for the variable In this case use c for
The verbal description is Twice the cost of plus the cost
of equals
C To write an equation write a numerical or expression for each quantity
and insert an equal sign in the appropriate place An equation is
Reflect
1 How can you use a verbal model to write an equation for the situation described
Module 2 55 Lesson 2
22 Creating and Solving EquationsEssential Question How do you use an equation to model and solve a real-world problem
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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igital
Vision
Getty Im
ages
2 Could you write a different equation to describe the situation Explain your reasoning
Explain 1 Creating and Solving Equations Involving the Distributive Property
When you create an equation to model a real-world problem your equation may involve the Distributive Property When you solve a real-world problem you should always check that your answer makes sense
Example 1 Write and solve an equation to solve each problem
A Aaron and Alice are bowling Alicersquos score is twice the difference of Aaronrsquos score and 5 The sum of their scores is 320 Find each studentrsquos bowling score
Write a verbal description of the basic situation
The sum of Aaronrsquos score and Alicersquos score is 320
Choose a variable for the unknown quantity and write an equation to model the detailed situation
Let a represent Aaronrsquos score Then 2 (a - 5) represents Alicersquos score
a + 2 (a - 5) = 320
Solve the equation for a
a + 2 (a - 5) = 320
a + 2a - 10 = 320 Distributive Property
3a - 10 = 320
3a - 10 + 10 = 320 + 10 Addition Property of Equality
3a = 330
3a _ 3 = 330 _ 3 Division Property of Equality
a = 110
So Aaronrsquos score is 110 and Alicersquos score is 2 (a - 5) = 2 (110 - 5) = 2 (105) = 210
Check that the answer makes sense
110 + 210 = 320 so the answer makes sense
B Mari Carlos and Amanda collect stamps Carlos has five more stamps than Mari and Amanda has three times as many stamps as Carlos Altogether they have 100 stamps Find the number of stamps each person has
Write a verbal description of the basic situation
Module 2 56 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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Choose a variable for the unknown quantity and write an equation to model the detailed situation
Let s represent the number of stamps Mari has Then Carlos has stamps
and Amanda has stamps
s + + 3 ( ) =
Solve the equation for s
s + + 3 ( ) =
s + s + 5 + 3s + = Distributive Property
+ = Combine like terms
s = Subtraction Property of Equality
s = Division Property of Equality
So Mari has stamps Carlos has stamps and Amanda
has stamps
Check that the answer makes sense
+ + = the answer makes sense
=
Reflect
3 Would a fractional answer make sense in this situation
4 Discussion What might it mean if a check revealed that the answer to a real-world problem did not make sense
Module 2 57 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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Your Turn
Write and solve an equation to solve the problem
5 A rectangular garden is fenced on all sides with 256 feet of fencing The garden is 8 feet longer than it is wide Find the length and width of the garden
Explain 2 Creating and Solving Equations with Variables on Both Sides
In some equations variables appear on both sides You can use the properties of equality to collect the variable terms so that they all appear on one side of the equation
Example 2 Write and solve an equation to solve each problem
A Janine has job offers at two companies One company offers a starting salary of $28000 with a raise of $3000 each year The other company offers a starting salary of $36000 with a raise of $2000 each year In how many years would Janinersquos salary be the same with both companies What will the salary be
Write a verbal description of the basic situation
Let n represent the number of years it takes for the salaries to be equal
Base Salary A plus $3000 per year raise = Base Salary B + $2000 per year raise
28000 + 3000n = 36000 + 2000n
28000 + 3000n - 2000n = 36000 + 2000n - 2000n Subtraction Property of Equality
28000 + 1000n = 36000 Combine like terms
28000 + 1000n - 28000 = 36000 - 28000 Subtraction Property of Equality
1000n = 8000 1000n _ 1000 = 8000 _ 1000 Division Property of Equality
n = 8
28000 + 3000 (8) = 36000 + 2000 (8)
52000 = 52000
In 8 years the salaries offered by both companies will be $52000
(w + 8) feet
w feet
Module 2 58 Lesson 2
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B One moving company charges $800 plus $16 per hour Another moving company charges $720 plus $21 per hour At what number of hours will the charge by both companies be the same What is the charge
Write a verbal description of the basic situation Let t represent the number of hours that the move takes
Moving Charge A plus $16 per hour = Moving Charge B plus $21 per hour
800 + t = 720 + t
800 + t - t = 720 + t - t Subtraction Property of Equality
800 = 720 + t
800 - 720 = 720 + t - 720 Subtraction Property of Equality
= t
_ = t _
Division Property of Equality
t =
The charges are the same for a job that takes hours
Substitute the value 16 in the original equation
800 + 16t = 720 + 21t
800 + 16 ( ) = 720 + 21 ( ) 800 + = 720 +
=
After hours the moving charge for both companies will be
Reflect
6 Suppose you collected the variable terms on the other side of the equal sign to solve the equation Would that affect the solution
Module 2 59 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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Your Turn
Write and solve an equation to solve each problem7 Claire bought just enough fencing to enclose either a
rectangular garden or a triangular garden as shown The two gardens have the same perimeter How many feet of fencing did she buy
8 A veterinarian is changing the diets of two animals Simba and Cuddles Simba currently consumes 1200 Calories per day That number will increase by 100 Calories each day Cuddles currently consumes 3230 Calories a day That number will decrease by 190 Calories each day The patterns will continue until both animals are consuming the same number of Calories each day In how many days will that be How many Calories will each animal be consuming each day then
Explain 3 Constructing Equations from an Organized TableYou can use a table to organize information and see relationships
Example 3 Construct and solve an equation to solve the problem
Kim works 4 hours more each day than Jill does and Jack works 2 hours less each day than Jill does Over 2 days the number of hours Kim works is equal to the difference of 4 times the number of hours Jack works and the number of hours Jill works How many hours does each person work each day
Analyze Information
Identify the important information
bull Kim works hours more per day than Jill does
bull Jack works hours less per day than Jill does
Formulate a Plan
Make a table using the information given Let x be the number of hours Jill works in one day
Hours Worked Per Day Hours Worked Over 2 Days
Kim
Jill
Jack
Over 2 days the number of hours Kim works is equal to the difference of 4 times the number of hours Jack works and the number of hours Jill works
(3x - 3)(x - 3)
(2x - 1) (2x - 1)
2x
Module 2 60 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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Solve
2 (x + 4) = 4 2 (x - 2) - 2x
2 (x + 4) = (x - 2) - 2x Simplify
2x + = 8x - - 2x Distributive Property
2x + 8 = x - 16
2x + 8 + = 6x - 16 + Addition Property of Equality
2x + = 6x
2x + 24 - x = 6x - x Subtraction Property of Equality
24 = x
24 _ = x _ Division Property of Equality
= x
Jill works hours per day Kim works hours per day and Jack works
hours per day
Justify and Evaluate
Substitute x = 6 into the original equation
2 (6 + 4) = 4 2 (6 - 2) - 2x
2 ( ) = 8 ( ) - 2 ( ) =
Your Turn
Write and solve an equation to solve the problem
9 Lisa is 10 centimeters taller than her friend Ian Ian is 14 centimeters taller than Jim Every month their heights increase by 2 centimeters In 7 months the sum of Ianrsquos and Jimrsquos heights will be 170 centimeters more than Lisarsquos height How tall is Ian now
Height now Height after 7 months
Module 2 61 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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pany
Elaborate
10 How can you use properties to solve equations with variables on both sides
11 How is a table helpful when constructing equations
12 When solving a real-world problem to find a personrsquos age would a negative solution make sense Explain
13 Essential Question Check-In How do you write an equation to represent a real-world situation
bull Online Homeworkbull Hints and Helpbull Extra Practice
Write an equation for each description
1 The sum of 14 and a number is equal to 17 2 A number increased by 10 is 114
3 The difference between a number and 12 is 20 4 Ten times the sum of half a number and 6 is 8
5 Two-thirds a number plus 4 is 7 6 Tanmayi wants to raise $175 for a school fundraiser She has raised $120 so far How much more does she need to reach her goal
7 Hector is visiting a cousin who lives 350 miles away He has driven 90 miles How many more miles does he need to drive to reach his cousinrsquos home
8 The length of a rectangle is twice its width The perimeter of the rectangle is 126 feet
Evaluate Homework and Practice
Module 2 62 Lesson 2
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Pete
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imS
hutt
erst
ock
Write and solve an equation for each situation
9 In one baseball season Peter hit twice the difference of the number of home runs Alice hit and 6 Altogether they hit 18 home runs How many home runs did each player hit that season
10 The perimeter of a parallelogram is 72 meters The width of the parallelogram is 4 meters less than its length Find the length and the width of the parallelogram
11 One month Ruby worked 6 hours more than Isaac and Svetlana worked 4 times as many hours as Ruby Together they worked 126 hours Find the number of hours each person worked
12 In one day Annie traveled 5 times the sum of the number of hours Brian traveled and 2 Together they traveled 20 hours Find the number of hours each person traveled
13 Xian and his cousin Kai both collect stamps Xian has 56 stamps and Kai has 80 stamps The boys recently joined different stamp-collecting clubs Xianrsquos club will send him 12 new stamps per month Kairsquos club will send him 8 new stamps per month After how many months will Xian and Kai have the same number of stamps How many stamps will each have
14 Kenya plans to make a down payment plus monthly payments in order to buy a motorcycle At one dealer she would pay $2500 down and $150 each month At another dealer she would pay $3000 down and $125 each month After how many months would the total amount paid be the same for both dealers What would that amount be
ℓ meters
(ℓ - 4) meters
Module 2 63 Lesson 2
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15 Community Gym charges a $50 membership fee and a $55 monthly fee Workout Gym charges a $200 membership fee and a $45 monthly fee After how many months will the total amount of money paid to both gyms be the same What will the amount be
16 Tina is saving to buy a notebook computer She has two options The first option is to put $200 away initially and save $10 every month The second option is to put $100 away initially and save $30 every month After how many months would Tina save the same amount using either option How much would she save with either option
Use the table to answer each question
Starting Salary Yearly Salary Increase
Company A $24000 $3000
Company B $30000 $2400
Company C $36000 $2000
17 After how many years are the salaries offered by Company A and Company B the same
18 After how many years are the salaries offered by Company B and Company C the same
19 Paul started work at Company B ten years ago at the salary shown in the table At the same time Sharla started at Company C at the salary shown in the table Who earned more during the last year How much more
20 Georgersquos page contains twice as many typed words as Billrsquos page and Billrsquos page contains 50 fewer words than Charliersquos page If each person can type 60 words per minute after one minute the difference between twice the number of words on Billrsquos page and the number of words on Charliersquos page is 210 How many words did Billrsquos page contain initially Use a table to organize the information
Initial number of words
Total number of words after one minute
Module 2 64 Lesson 2
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pan
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21 Geometry Sammie bought just enough fencing to border either a rectangular plot or a square plot as shown The perimeters of the plots are the same How many meters of fencing did she buy
HOT Focus on Higher Order Thinking
22 Justify Reasoning Suppose you want to solve the equation 2a + b = 2a where a and b are nonzero real numbers Describe the solution to this equation Justify your description
23 Multi-step A patio in the shape of a rectangle is fenced on all sides with 134 feet of fencing The patio is 5 feet less wide than it is long
a What information can be used to solve the problem How can you find the information
b Describe how to find the area of the patio What is the area of the patio
24 Explain the Error Kevin and Brittany write an equation to represent the following relationship and both students solve their equation Who found the correct equation and solution Why is the other person incorrect
5 times the difference of a number and 20 is the same as half the sum of 4 more than 4 times a number
Kevin Brittany
5 (x - 20) = 1 _ 2 (4x + 4) 5 (20 + x) = 1 _ 2 (4x + 4)
5x - 100 = 2x + 2 100 - 5x = 2x + 2
3x - 100 = 2 100 - 7x = 2
3x = 102 -7x = -98
x = 34 x = 14
(3x + 2) meters
(x + 2) meters
(x + 2) meters
(x - 1) meters
ℓ feet
(ℓ - 5) feet
Module 2 65 Lesson 2
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25 What If Alexa and Zack are solving the following problem
The number of miles on Car A is 50 miles more than the number of miles on Car B and the number of miles on Car B is 30 miles more than the number of miles on Car C All the cars travel 50 miles in 1 hour After 1 hour twice the number of miles on Car A is 70 miles less than 3 times the number of miles on Car C How many miles were there on Car B initially
Alexa assumes there are m miles on Car B Zack assumes there are m miles on Car C Will Zackrsquos answer be the same as Alexarsquos answer Explain
Lesson Performance Task
Stacy Oliver and Jivesh each plan to put a certain amount of money into their savings accounts that earn simple interest of 6 per year Stacy puts $550 more than Jivesh and Oliver puts in 2 times as much as Jivesh After a year the amount in Stacyrsquos account is 2 times the sum of $212 and the amount in Oliverrsquos account How much does each person initially put into his or her account Who had the most money in his or her account after a year Who had the least Explain
Zackrsquos Table Initial Miles
Miles after One Hour
Alexarsquos Table Initial Miles
Miles after One Hour
Amount in Account Initially Amount in Account after One Year
Module 2 66 Lesson 2
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Name Class Date
Resource Locker
Explore Rearranging Mathematical FormulasLiteral Equations are equations that contain two or more variables There are many literal equations in the form of math science and engineering formulas These formulas may seem like they can only be solved for the variable that is isolated on one side of the formula By using inverse operations and the properties of equality a formula can be rearranged so any variable in the formula can be isolated It is no different than how equations are solved by using inverse operations and the properties of equality
How can you solve the equation 42 = 6x
A42 _ = 6x _ What is the reason for dividing
Why divide by
= x By rearranging the equation x was isolated and the solution was found
The mathematical formula for the volume of a rectangular prism B = Vh or V = ℓwh is a literal equation V represents volume ℓ represents length w represents width and h represents height Using inverse operations the formula can be rearranged to solve for any one of the variables that might be unknown Like solving for x a formula can be rearranged to isolate a variable
B In the formula V = ℓwh the variable h needs to be isolated
The operation of is used in the formula The inverse
operation should be used
to isolate
C V _____ = ℓwh _____
V _ =
The formula rearranged in this way can easily produce the height of the rectangular prism when the volume length and width are known
Reflect
1 Using the formula for a rectangular prism rewrite the formula to solve for ℓ
ℓw
h
Module 2 67 Lesson 3
23 Solving for a VariableEssential Question How do you rewrite formulas and literal equations
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hyAurora Ph
otosCorb
is
Explain 1 Rearranging Scientific FormulasUse inverse operations to isolate the unknown variable in a scientific formula
The formula for density is D = m __ V Lead has a very high density of 11340 kg m 3 Plastic foam has a very low density of 75 kg m 3 The formula for density can be rearranged to solve for V volume or m mass
Example 1
A A sinker on a fishing line is made of lead and has a volume of 0000015 m 3 What is the mass of the sinker
The density formula can be rearranged to isolate m the mass The values for volume and density can then be substituted into the formula to find the mass
D = m _ V
DV = ( m _ V ) V DV = m
(11340 kg m 3 ) (0000015 m 3 ) = m
017 kg asymp m
B The design for a life preserver requires 03 kilogram of plastic foam to provide proper buoyancy What is the volume of the plastic foam required
Rearrange the density formula to isolate V
D = m _ V
(D) V = m _ V
DV =
DV _ = m _
V =
Now substitute the given values
V = _
V = m 3
Your Turn
2 For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Determine the altitude in feet when t is -275 ∘F and g is 60 ∘F
Module 2 68 Lesson 3
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Explain 2 Rearranging Literal EquationsUsing inverse operations to rearrange literal equations can be applied to any formula The interest formula I = prt is another example of a literal equation In the formula I represents interest p the principal or the initial amount to which interest will be applied r the rate at which interest will be paid and t is the time in years
Example 2
A Find the number of years used in the calculation of a $1000 loan at an interest rate of 5 with interest totaling $600
Solve the formula for t
I = prt
I _ pr = prt
_ pr
I _ pr = t
Substitute the given values Since the interest rate is 5 r = 005$600 __
$1000 middot 005 = t
12 = t
So the length of time for the loan is 12 years
B Determine the interest rate for a $2000 loan that will be paid off in 4 years with interest totaling $640 In order to find the interest rate solve the formula for r
I = prt
I _ = prt _
_ = r
Now substitute the values and simplify
__
( ) ( ) = r
008 = r
So the interest rate is per year
Your Turn
3 The formula y = mx + b is the slope-intercept form of the equation of a line Solve the equation for m
Module 2 69 Lesson 3
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oug
hton Mifflin H
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bull Online Homeworkbull Hints and Helpbull Extra Practice
Solve for the indicated variable in each mathematical formula
1 C = 2πr for r 2 A = 1 __ 2 bh for b 3 y = mx + b for x
4 A = 1 __ 2 (a + b)h for h 5 V = πr2h for h 6 SA = 2πr2 + 2πrh for h
Solve for the indicated variable in each scientific formula
7 d = rt for t 8 PV = nRT for T
9 A = FV - OV _______ T for OV 10 C = Wtc _ 1000 for W
Evaluate Homework and Practice
Elaborate
4 Discussion What could be a reason for isolating a variable in a literal equation
5 Describe a situation in which a formula could be used more easily if it were rearranged Include the formula in your description
6 Essential Question Check-In How do you isolate a variable
Module 2 70 Lesson 3
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pan
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cean
C
orb
is
Solve for the indicated variable in each literal equation
11 2p + 5r = q for p 12 -10 = xy + z for x 13 a __ b = c for b
14 h - 4 _ j = k for j 15 x __ 5 - g = a for x 16 5p + 9c = p for c
17 2 __ 5 (z + 1) = y for z 18 g (h + 2 __ 3 ) = 1 for h 19 a(n - 3) + 8 = bn for n
20 Which is a possible way to rewrite the equation y = 3x + 3b to solve for b
A b = y - 3x
_ 3 C b = y - 3
_____ 3x
B b = 3(y - 3x) D b = x(y - 3)
21 Sports To find a baseball pitcherrsquos earned run average (ERA) you can use the formula Ei = 9r in which E represents ERA i represents the number of innings pitched and r represents the number of earned runs allowed Solve the equation for E What is a pitcherrsquos ERA if he allows 5 earned runs in 18 innings pitched
22 Meteorology For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Solve the equation for a If the atmospheric temperature is -655 ∘F and the ground temperature is 57 ∘F what is the altitude
Module 2 71 Lesson 3
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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arcourt Publishin
g Com
pany bull Im
age C
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Rand
y D
uch
aineA
lamy
HOT Focus on Higher Order Thinking
23 Explain the Error A student was asked to use the formula for the perimeter of a rectangle P = 2ℓ + 2w to solve for ℓ The student came up with an answer P - 2w = 2ℓ What error did the student make Explain Then solve for ℓ
24 Multi-Step The formula c = 5p + 215 relates c the total cost in dollars of hosting a birthday party at a skating rink to p the number of people attending If Alliersquos parents are willing to spend $300 for a party how many people can attend
25 Multi-Step The formula for the area of a triangle is A = 1 __ 2 bh in which b represents the length of thebase and h represents the height If a triangle has an area of 192 mm2 and the height is 12 mm what is the measure of the base
Lesson Performance TaskThe following table shows the average low temperatures in Fahrenheit for the city of Boston for several months during the year The formula F = 9 __ 5 C + 32 allows you to determine the temperature in Fahrenheit when given the temperature in Celsius
MonthTemperature in
FahrenheitTemperature in
Celsius
January 22deg
April 41deg
July 65deg
October 47deg
December 28deg
a Use the information given to determine the average low temperatures in Celsius
b Would it ever be possible for the temperature in Celsius to have a greater value than the temperature in Fahrenheit Explain why or why not
Module 2 72 Lesson 3
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
Name Class Date
Resource Locker
copy H
oug
hton
Mif
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Har
cour
t Pub
lishi
ng
Com
pan
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mag
e cr
edit
s copy
Patr
ick
Lan
eSo
mos
Imag
esC
orb
is
Explore Creating Inequalities from Verbal DescriptionsAn inequality is a statement that compares two expressions that are not strictly equal by using one of the following inequality signs
Symbol Meaning
lt is less than
le is less than or equal to
gt is greater than
ge is greater than or equal to
ne is not equal to
You have probably seen a sign at an amusement park saying something like ldquoYou must be at least 48 inches tall to ride this riderdquo This statement could be written as h ge 48 in where h represents the height of a person allowed to ride
Nora is planning a birthday party for her little sister Colleen Norarsquos budget will allow her to spend no more than $50 for party supplies Eight children including Colleen will attend the party and Nora wants to determine how much she could spend on party favors for each child She will also purchase a cake for $10 Write an inequality that represents the situation and find possible solutions
A First let c represent the cost of a party favor for each child Write an expression for the total cost of the party as a function of c
c +
B Which inequality symbol should be used to represent the phrase ldquono more thanrdquo
C Write the inequality that represents Norarsquos budget goal
8c + 10 le
D Suppose Nora finds party favors that cost $4 each Use a value of 4 for c and check to see if this inequality is true
8 middot 4 + 10 le 50
le 50
Module 2 73 Lesson 4
24 Creating and Solving Inequalities
Essential Question How do you write and solve an inequality that represents a real-world situation
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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pany
Is the inequality true
Could Nora buy $6 party favors for all of her guests without going over budget
Reflect
1 Why does an inequality represent Norarsquos budget calculation better than an equation
2 The solution set of an inequality consists of all values that make the statement true Describe the whole dollar amounts that are in the solution set for this situation
Explain 1 Creating and Solving Inequalities Involving the Distributive Property
You may need to use the Distributive Property before you can solve an inequality
Distributive Property If a b and c are real numbers then a(b + c) = ab + ac
The inequality sign must be reversed when multiplying or dividing both sides of an inequality by a negative number
Example 1
A Trina is buying 12 shirts for the drama club She will choose a style for the blank shirts and then pay an additional charge of $275 for each shirt to have the club logo If Trina cannot spend more than $99 how much can she spend on each blank shirt Write and solve an inequality to find the possible cost of each blank shirt
Let s represent the cost of each blank shirt
Write an inequality to represent the situation 12(s + 275) le 99
Use the Distributive Property 12s + 33 le 99
Subtraction Property of Inequality 12s + 33 - 33 le 99 - 33
Simplify 12s le 66
Division Property of Inequality 12s ___ 12 le 66 __ 12
Simplify s le 55
Module 2 74 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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oug
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Mif
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Har
cour
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lishi
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Com
pan
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Check your answer
Since s le 55 check a smaller number 12(5 + 275) le 99
Trina can order blank shirts that cost $550 or less 93 le 99 true
B Sergio needs to buy gifts for 8 friends He wants to give the same gift to all his friends and he plans to have the gifts wrapped for an additional charge of $150 each If Sergio spends at least $70 he will receive free shipping on his order Write and solve an inequality to determine how much Sergio needs to spend on each gift in order to receive free shipping
Let g be the cost of one gift
Write an inequality to represent the situation ( g + ) ge 70
Use the Distributive Property g + ge 70
Subtraction Property of Inequality g + 12 - ge 70 -
Simplify 8g ge
Division Property of Inequality 8g _
ge 58 _
Simplify g ge
Check your answer
Since g ge 725 check a larger number 8(8 + 150) ge 70
Sergio must spend at least on each gift ge 70
Reflect
3 Discussion Why is the first step in solving the inequality to use the Distributive Property instead of working inside the parentheses
Your Turn
4 Zachary is planning to send a video game to each of his two brothers If he buys the same game for both brothers and pays $475 to ship each game how much can he spend on each game without spending more than $100 Write and solve an inequality for this situation
Solve each inequality
5 4 _ 3 (6x + 9) lt 4 6 -2 ( 1 _ 4 x + 2 ) ge 5
Module 2 75 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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Explain 2 Creating and Solving Inequalities with Variables on Both Sides
Some inequalities have variable terms on both sides of the inequality symbol You can solve these inequalities the same way you solved equations with variables on both sides Use the properties of inequality to collect all the variable terms on one side and all the constant terms on the other side
Example 2
A The Daily Info charges a fee of $650 plus $80 per week to run an ad The Peoplersquos Paper charges $145 per week For how many weeks must an ad run for the total cost at the Daily Info to be less expensive than the cost at the Peoplersquos Paper Let w be the number of weeks the ad runs in the paper
Write an inequality to represent the situation 650 + 80w lt 145w
Subtraction Property of Inequality 650 + 80w - 80w lt 145w - 80w
Simplify 650 lt 65w
Division Property of Inequality 650 _ 65 lt 65w _ 65
Simplify 10 lt w
The total cost at the Daily Info is less than the cost at the Peoplersquos Paper if the ad runs for more than 10 weeks
B The Home Cleaning Company charges $312 to power-wash the siding of a house plus $12 for each window Power Clean charges $36 per window and the price includes power-washing the siding How many windows must a house have to make the total cost from The Home Cleaning Company less expensive than Power Clean Let w be the number of windows
Write an inequality to represent the situation +12w lt 36w
Subtraction Property of Inequality 312 + 12w - lt 36w -
Simplify 312 lt
Division Property of Inequality 312 _ lt 24w _
Simplify lt w
A house must have more than 13 windows for The Home Cleaning Company to be less expensive than Power Clean
Reflect
7 How would the final inequality change if you divided by ndash24 in the next to last step
Your Turn
8 The school band will sell pizzas to raise money for new uniforms The supplier charges $100 plus $4 per pizza The band members sell the pizzas for $7 each Write and solve an inequality to find how many pizzas the band members will have to sell to make a profit
Module 2 76 Lesson 4
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cour
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Elaborate
9 Which inequality symbol would you use to represent the following words or phrases Can you come up with more examples
a at most b farther than c younger than d up to
10 Discussion How are the steps to solving an inequality similar to those for solving an equation How are they different
11 Essential Question Check-In How can you write an inequality that represents a real-world situation
Write an inequality that represents the description and then solve
1 Max has more than 5 carrots (number of carrots Max has = c)
2 Brigitte is shorter than 5 feet (Brigittersquos height = h)
3 Twice a number (x) is less than 10 4 Six more than five times a number (x) is at least twenty-one
5 Dave has $15 to spend on an $8 book and two birthday cards (c) for his friends How much can he spend on each card if he buys the same card for each friend
6 Toni can carry up to 18 lb in her backpack Her lunch weighs 1 lb her gym clothes weigh 2 lb and her books (b) weigh 3 lb each How many books can she carry in her backpack
Evaluate Homework and Practice
bull Online Homeworkbull Hints and Helpbull Extra Practice
Module 2 77 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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oug
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arcourt Publishin
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pany
Solve each inequality
7 3 (x - 2) gt -3 8 5 + 5 (x + 4) le 20 9 3 + 1 _ 2 (3 - x) lt -7
10 3 (x + 6) - 2 (x + 2) ge 10 11 5 (3 - x) -4 (2 - 3x) gt 2 12 1 _ 2 (4x - 2) - 2 _ 3 (6x + 9) le 4
13 x + 1 gt -5 (7 - 2x) 14 5 _ 3 (6x + 3) le 2x - 7
15 2x le - 2 __ 3 (4x + 4) 16 1 __ 2 (-2x - 10) gt 3 (4 - 6x)
17 -5 - 3x ge 2 (10 + 2x) + 3 18 -3 (9x + 20) ge 15x - 20
19 8 ( 1 _ 4 x - 3) + 24 lt 4 ( x + 5 ) 20 6x - 2 (x + 2) gt 2 - 3 (x + 3)
Module 2 78 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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pan
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21 Physics A crane cable can support a maximum load of 15000 kg If a bucket has a mass of 2000 kg and gravel has a mass of 1500 kg for every cubic meter how many cubic meters of gravel (g) can be safely lifted by the crane
22 Find the solution set of each inequality below and then determine which inequalities have the same solution set as 1 _ 3 ( -5x - 3 ) lt 14
a 1 _ 3 (5x + 3) gt -14 b 2 _ 5 (10x + 20) gt 44
c - 2 _ 5 (10x + 20) lt -44 d - 1 _ 3 (5x + 3) lt 14
e 2 _ 5 (10x - 20) gt -44 f 1 _ 3 (5x + 3) lt -14
HOT Focus on Higher Order Thinking
23 Explain the Error Sven is trying to find the maximum amount of time he can spend practicing the five scales of piano music he is supposed to be working on He has 60 minutes to practice piano and would like to spend at least 35 minutes playing songs instead of practicing scales So Sven sets up the following inequality where t is the number of minutes he spends on each scale and solves it
60 - 5t le 35-5t le -25
t ge 5
Sven has concluded that he should spend 5 minutes or more on each scale Is this correct If not what mistake did he make Then solve for the correct answer
Module 2 79 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
24 Critical Thinking Anika wants to determine the maximum number of tulip bulbs (t) she can purchase if each bulb costs $150 She will also need to purchase separate pots for each bulb at $125 each and a bag of potting soil for $1000 Set up an inequality to determine how many tulip bulbs Anika can purchase without spending more than $2000 and solve it Can Anika buy exactly enough bulbs and pots to spend the full $2000 Explain Can you think of a better inequality to describe the answer
25 Geometry The area of the triangle shown is no more than 10 square inches
a Write an inequality that can be used to find x
b Solve the inequality from part a c What is the maximum height of the triangle
Lesson Performance TaskWhen planning an airplane route the trip planner must be careful to consider the range the aircraft can travel and the availability of airports to stop and refuel
A large commercial jet airplane burns approximately 5 gallons of fuel per mile flown plus about 8500 gallons of fuel per trip to reach cruising altitude With a useable fuel capacity of 50000 gallons (there is additional fuel reserved for emergencies) describe the acceptable distance for which an airline could establish a non-stop flight
For flights originating from Chicago determine which cities could be safely reached by a non-stop flight
City Distance from Chicago (miles)
Bangalore India 8530
Jakarta Indonesia 9810
Johannesburg South Africa 8680
Moscow Russia 4970
Paris France 4130
Perth Australia 10970
Tokyo Japan 6300
copy H
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eva O
lesiaShutterstock
(2x - 3) in
4 in
Module 2 80 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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Har
cour
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Name Class Date
Resource Locker
Explore Truth Tables and Compound StatementsA compound statement is formed by combining two or more simple statements A compound statement can be true or false A compound statement involving AND is true when both simple statements are true A compound statement involving OR is true when either one simple statement or both are true
A Complete the truth table
P QP
True or FalseQ
True or FalseP AND Q
True or False
A dog is a mammal Red is a color
A dog is a mammal Red is not a color
A dog is a fish Red is a color
A dog is a fish Red is not a color
B P AND Q is true when
C Complete the truth table
P QP
True or FalseQ
True or FalseP OR Q
True or False
1 is an odd number 2 is an even number
1 is an odd number 2 is an odd number
1 is an even number 2 is an even number
1 is an even number 2 is an odd number
D P OR Q is true when
Reflect
1 Give two simple statements P and Q for which P AND Q is false and P OR Q is true
Module 2 81 Lesson 5
25 Creating and Solving Compound Inequalities
Essential Question How can you solve a compound inequality and graph the solution set
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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Explain 1 Solving Compound Inequalities Involving ANDCombining two or more simple inequalities forms a compound inequality The graph of a compound inequality involving AND is the intersection or the overlapping region of the simple inequality graphs
Compound Inequalities AND
Words Algebra Graph
All real numbers greater than 2AND less than 6
x gt 2 AND x lt 62 lt x lt 6
All real numbers greater than or equal to 2 AND less than or equal to 6
x ge 2 AND x le 62 le x le 6
Example 1 Solve each compound inequality and graph the solutions
A 4 le x + 2 le 8
4 le x + 2 AND x + 2 le 8 Write the compound inequality using AND
4 - 2 le x + 2 - 2 x + 2 - 2 le 8 - 2 Subtract 2 from both sides of each simple inequality
2 le x x le 6 Simplify
Graph 2 le x
Graph x le 6
Graph the intersection by finding where the two graphs overlap
B -5 le 2x + 3 lt 9
-5 - le 2x + 3 - lt 9 - Subtract from each part of the inequality
le 2x lt Simplify
-8 _ le 2x _ lt 6 _ Divide each part of the inequality by
le x lt Simplify
Graph -4 le x
Graph x lt 3
Graph the intersection by finding where the two graphs overlap -1 0 1 2 3 4 5-5-4 -3 -2
0 2 4 6 8 10 12-8-6-4 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 82 Lesson 5
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Reflect
2 Discussion Explain why 2 le x le 6 can be considered the short method for writing the AND compound inequality x ge 2 AND x le 6
YourTurn
Solve each compound inequality and graph the solutions
3 -2 lt x - 3 lt 5
4 -10 lt 3x + 2 le 8
Explain 2 Solving Compound Inequalities Involving ORThe graph of a compound inequality involving OR is the union or the combined region of the simple inequality graphs
Compound Inequalities OR
Words Algebra Graph
All real numbers less than 2OR greater than 6
x lt 2 OR x gt 6
All real numbers less than or equal to 2OR greater than or equal to 6
x le 2 OR x ge 6
-1 0 1 2 3 4 5-5-4 -3 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 83 Lesson 5
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Example 2 Solve each compound inequality and graph the solutions
A -4 + x gt 1 OR -4 + x lt -3
-4 + x gt 1 OR -4 + x lt -3 Write the compound inequality using OR
-4 + 4 + x gt 1 + 4 -4 + 4 + x lt -3 + 4 Add 4 to both sides of each simple inequality
x gt 5 x lt 1 Simplify
Graph x gt 5
Graph x lt 1
Graph the union by combining the graphs
B 2x le 6 OR 3x gt 12
2x le 6 OR 3x gt 12 Write the compound inequality using OR
2x _ le 6 _ OR 3x _ gt 12 _ Divide the first simple inequality by
x le OR x gt
Graph x le 3
Graph x gt 4
Graph the union by combining the graphs
Reflect
5 Critical Thinking What kind of compound inequality has no solution
Divide the second simple inequality by
Simplify
0 1 2 3 4 5 6-4 -3 -2 -1
-0 1 2 3 4 5 6-4 -3 -2 -1
Module 2 84 Lesson 5
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Your Turn
Solve each compound inequality and graph the solutions
6 x - 5 ge -2 OR x -5 le -6
7 4x -1 lt 15 OR 8x ge 48
Explain 3 Creating Compound Inequalities From GraphsGiven a number line graph with a solution set graphed you can create a compound inequality to fit the graph
Example 3 Write the compound inequality shown by each graph
A
The shaded portion of the graph is not between two values so the compound inequality involves OR
On the left the graph shows an arrow pointing left from -1 and a solid circle so use le
The inequality is x le -1
On the right the graph shows an arrow pointing right from 7 and a solid circle so use ge
The inequality is x ge 7
The compound inequality is x le -1 OR x ge 7
B
The graph is shaded between the values and so the compound inequality involves AND
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The compound inequality is
-1 0 1 2 3 4 5-5-4 -3 -2
4 5 6 7 8 9 100 1 2 3
2 3 4 5 6 7 8-2 -1 0 1
10 2 3 4 5 6 7 8 9-1
Module 2 85 Lesson 5
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oug
hton Mifflin H
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Reflect
8 What is a short method to write the compound inequality x ge 0 AND x lt 6
Your Turn
Write the compound inequality shown by each graph
9
10
Explain 4 Expressing Acceptable Levels with Compound Inequalities
You can express quality-controls levels in real-world problems using compound inequalities
Example 4 Write a compound inequality to represent the indicated quality-control level and graph the solutions
A The recommended pH level for swimming pool water is between 72 and 76 inclusive
Let p be the pH level of swimming pool water
72 is less than or equal to pH level is less than or equal to 76
72 le p le 76
The compound inequality is 72 le p le 76
Graph the solutions
0-10 -8-9 -7-6 -5-4 -3 -2 -1
71 72 73 74 75 76 77 78 79 8070
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 86 Lesson 5
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oug
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B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
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oug
hton Mifflin H
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bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
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oug
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Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
arcourt Publishin
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age C
redits copy
Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
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oug
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pan
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bik
erid
erlo
nd
onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
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oug
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The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
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oug
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Name Class Date
Resource Locker
Explore Creating Equations from Verbal Descriptions
You can use what you know about writing algebraic expressions to write an equation that represents a real-world situation
Suppose Cory and his friend Walter go to a movie Each of their tickets costs the same amount and they share a frozen yogurt that costs $550 The total amount they spend is $1990 How can you write an equation that describes the situation
A Identify the important information
The word tells you that the relationship describes an equation
The word total tells you that the operation involved in the relationship is
What numerical information do you have
What is the unknown quantity
B Write a verbal description
Choose a name for the variable In this case use c for
The verbal description is Twice the cost of plus the cost
of equals
C To write an equation write a numerical or expression for each quantity
and insert an equal sign in the appropriate place An equation is
Reflect
1 How can you use a verbal model to write an equation for the situation described
Module 2 55 Lesson 2
22 Creating and Solving EquationsEssential Question How do you use an equation to model and solve a real-world problem
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
arcourt Publishin
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age C
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igital
Vision
Getty Im
ages
2 Could you write a different equation to describe the situation Explain your reasoning
Explain 1 Creating and Solving Equations Involving the Distributive Property
When you create an equation to model a real-world problem your equation may involve the Distributive Property When you solve a real-world problem you should always check that your answer makes sense
Example 1 Write and solve an equation to solve each problem
A Aaron and Alice are bowling Alicersquos score is twice the difference of Aaronrsquos score and 5 The sum of their scores is 320 Find each studentrsquos bowling score
Write a verbal description of the basic situation
The sum of Aaronrsquos score and Alicersquos score is 320
Choose a variable for the unknown quantity and write an equation to model the detailed situation
Let a represent Aaronrsquos score Then 2 (a - 5) represents Alicersquos score
a + 2 (a - 5) = 320
Solve the equation for a
a + 2 (a - 5) = 320
a + 2a - 10 = 320 Distributive Property
3a - 10 = 320
3a - 10 + 10 = 320 + 10 Addition Property of Equality
3a = 330
3a _ 3 = 330 _ 3 Division Property of Equality
a = 110
So Aaronrsquos score is 110 and Alicersquos score is 2 (a - 5) = 2 (110 - 5) = 2 (105) = 210
Check that the answer makes sense
110 + 210 = 320 so the answer makes sense
B Mari Carlos and Amanda collect stamps Carlos has five more stamps than Mari and Amanda has three times as many stamps as Carlos Altogether they have 100 stamps Find the number of stamps each person has
Write a verbal description of the basic situation
Module 2 56 Lesson 2
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oug
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pan
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Choose a variable for the unknown quantity and write an equation to model the detailed situation
Let s represent the number of stamps Mari has Then Carlos has stamps
and Amanda has stamps
s + + 3 ( ) =
Solve the equation for s
s + + 3 ( ) =
s + s + 5 + 3s + = Distributive Property
+ = Combine like terms
s = Subtraction Property of Equality
s = Division Property of Equality
So Mari has stamps Carlos has stamps and Amanda
has stamps
Check that the answer makes sense
+ + = the answer makes sense
=
Reflect
3 Would a fractional answer make sense in this situation
4 Discussion What might it mean if a check revealed that the answer to a real-world problem did not make sense
Module 2 57 Lesson 2
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oug
hton Mifflin H
arcourt Publishin
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pany
Your Turn
Write and solve an equation to solve the problem
5 A rectangular garden is fenced on all sides with 256 feet of fencing The garden is 8 feet longer than it is wide Find the length and width of the garden
Explain 2 Creating and Solving Equations with Variables on Both Sides
In some equations variables appear on both sides You can use the properties of equality to collect the variable terms so that they all appear on one side of the equation
Example 2 Write and solve an equation to solve each problem
A Janine has job offers at two companies One company offers a starting salary of $28000 with a raise of $3000 each year The other company offers a starting salary of $36000 with a raise of $2000 each year In how many years would Janinersquos salary be the same with both companies What will the salary be
Write a verbal description of the basic situation
Let n represent the number of years it takes for the salaries to be equal
Base Salary A plus $3000 per year raise = Base Salary B + $2000 per year raise
28000 + 3000n = 36000 + 2000n
28000 + 3000n - 2000n = 36000 + 2000n - 2000n Subtraction Property of Equality
28000 + 1000n = 36000 Combine like terms
28000 + 1000n - 28000 = 36000 - 28000 Subtraction Property of Equality
1000n = 8000 1000n _ 1000 = 8000 _ 1000 Division Property of Equality
n = 8
28000 + 3000 (8) = 36000 + 2000 (8)
52000 = 52000
In 8 years the salaries offered by both companies will be $52000
(w + 8) feet
w feet
Module 2 58 Lesson 2
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oug
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cour
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pan
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B One moving company charges $800 plus $16 per hour Another moving company charges $720 plus $21 per hour At what number of hours will the charge by both companies be the same What is the charge
Write a verbal description of the basic situation Let t represent the number of hours that the move takes
Moving Charge A plus $16 per hour = Moving Charge B plus $21 per hour
800 + t = 720 + t
800 + t - t = 720 + t - t Subtraction Property of Equality
800 = 720 + t
800 - 720 = 720 + t - 720 Subtraction Property of Equality
= t
_ = t _
Division Property of Equality
t =
The charges are the same for a job that takes hours
Substitute the value 16 in the original equation
800 + 16t = 720 + 21t
800 + 16 ( ) = 720 + 21 ( ) 800 + = 720 +
=
After hours the moving charge for both companies will be
Reflect
6 Suppose you collected the variable terms on the other side of the equal sign to solve the equation Would that affect the solution
Module 2 59 Lesson 2
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oug
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Your Turn
Write and solve an equation to solve each problem7 Claire bought just enough fencing to enclose either a
rectangular garden or a triangular garden as shown The two gardens have the same perimeter How many feet of fencing did she buy
8 A veterinarian is changing the diets of two animals Simba and Cuddles Simba currently consumes 1200 Calories per day That number will increase by 100 Calories each day Cuddles currently consumes 3230 Calories a day That number will decrease by 190 Calories each day The patterns will continue until both animals are consuming the same number of Calories each day In how many days will that be How many Calories will each animal be consuming each day then
Explain 3 Constructing Equations from an Organized TableYou can use a table to organize information and see relationships
Example 3 Construct and solve an equation to solve the problem
Kim works 4 hours more each day than Jill does and Jack works 2 hours less each day than Jill does Over 2 days the number of hours Kim works is equal to the difference of 4 times the number of hours Jack works and the number of hours Jill works How many hours does each person work each day
Analyze Information
Identify the important information
bull Kim works hours more per day than Jill does
bull Jack works hours less per day than Jill does
Formulate a Plan
Make a table using the information given Let x be the number of hours Jill works in one day
Hours Worked Per Day Hours Worked Over 2 Days
Kim
Jill
Jack
Over 2 days the number of hours Kim works is equal to the difference of 4 times the number of hours Jack works and the number of hours Jill works
(3x - 3)(x - 3)
(2x - 1) (2x - 1)
2x
Module 2 60 Lesson 2
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oug
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pan
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Solve
2 (x + 4) = 4 2 (x - 2) - 2x
2 (x + 4) = (x - 2) - 2x Simplify
2x + = 8x - - 2x Distributive Property
2x + 8 = x - 16
2x + 8 + = 6x - 16 + Addition Property of Equality
2x + = 6x
2x + 24 - x = 6x - x Subtraction Property of Equality
24 = x
24 _ = x _ Division Property of Equality
= x
Jill works hours per day Kim works hours per day and Jack works
hours per day
Justify and Evaluate
Substitute x = 6 into the original equation
2 (6 + 4) = 4 2 (6 - 2) - 2x
2 ( ) = 8 ( ) - 2 ( ) =
Your Turn
Write and solve an equation to solve the problem
9 Lisa is 10 centimeters taller than her friend Ian Ian is 14 centimeters taller than Jim Every month their heights increase by 2 centimeters In 7 months the sum of Ianrsquos and Jimrsquos heights will be 170 centimeters more than Lisarsquos height How tall is Ian now
Height now Height after 7 months
Module 2 61 Lesson 2
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oug
hton Mifflin H
arcourt Publishin
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pany
Elaborate
10 How can you use properties to solve equations with variables on both sides
11 How is a table helpful when constructing equations
12 When solving a real-world problem to find a personrsquos age would a negative solution make sense Explain
13 Essential Question Check-In How do you write an equation to represent a real-world situation
bull Online Homeworkbull Hints and Helpbull Extra Practice
Write an equation for each description
1 The sum of 14 and a number is equal to 17 2 A number increased by 10 is 114
3 The difference between a number and 12 is 20 4 Ten times the sum of half a number and 6 is 8
5 Two-thirds a number plus 4 is 7 6 Tanmayi wants to raise $175 for a school fundraiser She has raised $120 so far How much more does she need to reach her goal
7 Hector is visiting a cousin who lives 350 miles away He has driven 90 miles How many more miles does he need to drive to reach his cousinrsquos home
8 The length of a rectangle is twice its width The perimeter of the rectangle is 126 feet
Evaluate Homework and Practice
Module 2 62 Lesson 2
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oug
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Mif
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Har
cour
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Com
pan
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mag
e C
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(t)copy
Pete
r K
imS
hutt
erst
ock
Write and solve an equation for each situation
9 In one baseball season Peter hit twice the difference of the number of home runs Alice hit and 6 Altogether they hit 18 home runs How many home runs did each player hit that season
10 The perimeter of a parallelogram is 72 meters The width of the parallelogram is 4 meters less than its length Find the length and the width of the parallelogram
11 One month Ruby worked 6 hours more than Isaac and Svetlana worked 4 times as many hours as Ruby Together they worked 126 hours Find the number of hours each person worked
12 In one day Annie traveled 5 times the sum of the number of hours Brian traveled and 2 Together they traveled 20 hours Find the number of hours each person traveled
13 Xian and his cousin Kai both collect stamps Xian has 56 stamps and Kai has 80 stamps The boys recently joined different stamp-collecting clubs Xianrsquos club will send him 12 new stamps per month Kairsquos club will send him 8 new stamps per month After how many months will Xian and Kai have the same number of stamps How many stamps will each have
14 Kenya plans to make a down payment plus monthly payments in order to buy a motorcycle At one dealer she would pay $2500 down and $150 each month At another dealer she would pay $3000 down and $125 each month After how many months would the total amount paid be the same for both dealers What would that amount be
ℓ meters
(ℓ - 4) meters
Module 2 63 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
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pany
15 Community Gym charges a $50 membership fee and a $55 monthly fee Workout Gym charges a $200 membership fee and a $45 monthly fee After how many months will the total amount of money paid to both gyms be the same What will the amount be
16 Tina is saving to buy a notebook computer She has two options The first option is to put $200 away initially and save $10 every month The second option is to put $100 away initially and save $30 every month After how many months would Tina save the same amount using either option How much would she save with either option
Use the table to answer each question
Starting Salary Yearly Salary Increase
Company A $24000 $3000
Company B $30000 $2400
Company C $36000 $2000
17 After how many years are the salaries offered by Company A and Company B the same
18 After how many years are the salaries offered by Company B and Company C the same
19 Paul started work at Company B ten years ago at the salary shown in the table At the same time Sharla started at Company C at the salary shown in the table Who earned more during the last year How much more
20 Georgersquos page contains twice as many typed words as Billrsquos page and Billrsquos page contains 50 fewer words than Charliersquos page If each person can type 60 words per minute after one minute the difference between twice the number of words on Billrsquos page and the number of words on Charliersquos page is 210 How many words did Billrsquos page contain initially Use a table to organize the information
Initial number of words
Total number of words after one minute
Module 2 64 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
copy H
oug
hton
Mif
flin
Har
cour
t Pub
lishi
ng
Com
pan
y
21 Geometry Sammie bought just enough fencing to border either a rectangular plot or a square plot as shown The perimeters of the plots are the same How many meters of fencing did she buy
HOT Focus on Higher Order Thinking
22 Justify Reasoning Suppose you want to solve the equation 2a + b = 2a where a and b are nonzero real numbers Describe the solution to this equation Justify your description
23 Multi-step A patio in the shape of a rectangle is fenced on all sides with 134 feet of fencing The patio is 5 feet less wide than it is long
a What information can be used to solve the problem How can you find the information
b Describe how to find the area of the patio What is the area of the patio
24 Explain the Error Kevin and Brittany write an equation to represent the following relationship and both students solve their equation Who found the correct equation and solution Why is the other person incorrect
5 times the difference of a number and 20 is the same as half the sum of 4 more than 4 times a number
Kevin Brittany
5 (x - 20) = 1 _ 2 (4x + 4) 5 (20 + x) = 1 _ 2 (4x + 4)
5x - 100 = 2x + 2 100 - 5x = 2x + 2
3x - 100 = 2 100 - 7x = 2
3x = 102 -7x = -98
x = 34 x = 14
(3x + 2) meters
(x + 2) meters
(x + 2) meters
(x - 1) meters
ℓ feet
(ℓ - 5) feet
Module 2 65 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
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25 What If Alexa and Zack are solving the following problem
The number of miles on Car A is 50 miles more than the number of miles on Car B and the number of miles on Car B is 30 miles more than the number of miles on Car C All the cars travel 50 miles in 1 hour After 1 hour twice the number of miles on Car A is 70 miles less than 3 times the number of miles on Car C How many miles were there on Car B initially
Alexa assumes there are m miles on Car B Zack assumes there are m miles on Car C Will Zackrsquos answer be the same as Alexarsquos answer Explain
Lesson Performance Task
Stacy Oliver and Jivesh each plan to put a certain amount of money into their savings accounts that earn simple interest of 6 per year Stacy puts $550 more than Jivesh and Oliver puts in 2 times as much as Jivesh After a year the amount in Stacyrsquos account is 2 times the sum of $212 and the amount in Oliverrsquos account How much does each person initially put into his or her account Who had the most money in his or her account after a year Who had the least Explain
Zackrsquos Table Initial Miles
Miles after One Hour
Alexarsquos Table Initial Miles
Miles after One Hour
Amount in Account Initially Amount in Account after One Year
Module 2 66 Lesson 2
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Name Class Date
Resource Locker
Explore Rearranging Mathematical FormulasLiteral Equations are equations that contain two or more variables There are many literal equations in the form of math science and engineering formulas These formulas may seem like they can only be solved for the variable that is isolated on one side of the formula By using inverse operations and the properties of equality a formula can be rearranged so any variable in the formula can be isolated It is no different than how equations are solved by using inverse operations and the properties of equality
How can you solve the equation 42 = 6x
A42 _ = 6x _ What is the reason for dividing
Why divide by
= x By rearranging the equation x was isolated and the solution was found
The mathematical formula for the volume of a rectangular prism B = Vh or V = ℓwh is a literal equation V represents volume ℓ represents length w represents width and h represents height Using inverse operations the formula can be rearranged to solve for any one of the variables that might be unknown Like solving for x a formula can be rearranged to isolate a variable
B In the formula V = ℓwh the variable h needs to be isolated
The operation of is used in the formula The inverse
operation should be used
to isolate
C V _____ = ℓwh _____
V _ =
The formula rearranged in this way can easily produce the height of the rectangular prism when the volume length and width are known
Reflect
1 Using the formula for a rectangular prism rewrite the formula to solve for ℓ
ℓw
h
Module 2 67 Lesson 3
23 Solving for a VariableEssential Question How do you rewrite formulas and literal equations
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otosCorb
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Explain 1 Rearranging Scientific FormulasUse inverse operations to isolate the unknown variable in a scientific formula
The formula for density is D = m __ V Lead has a very high density of 11340 kg m 3 Plastic foam has a very low density of 75 kg m 3 The formula for density can be rearranged to solve for V volume or m mass
Example 1
A A sinker on a fishing line is made of lead and has a volume of 0000015 m 3 What is the mass of the sinker
The density formula can be rearranged to isolate m the mass The values for volume and density can then be substituted into the formula to find the mass
D = m _ V
DV = ( m _ V ) V DV = m
(11340 kg m 3 ) (0000015 m 3 ) = m
017 kg asymp m
B The design for a life preserver requires 03 kilogram of plastic foam to provide proper buoyancy What is the volume of the plastic foam required
Rearrange the density formula to isolate V
D = m _ V
(D) V = m _ V
DV =
DV _ = m _
V =
Now substitute the given values
V = _
V = m 3
Your Turn
2 For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Determine the altitude in feet when t is -275 ∘F and g is 60 ∘F
Module 2 68 Lesson 3
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Explain 2 Rearranging Literal EquationsUsing inverse operations to rearrange literal equations can be applied to any formula The interest formula I = prt is another example of a literal equation In the formula I represents interest p the principal or the initial amount to which interest will be applied r the rate at which interest will be paid and t is the time in years
Example 2
A Find the number of years used in the calculation of a $1000 loan at an interest rate of 5 with interest totaling $600
Solve the formula for t
I = prt
I _ pr = prt
_ pr
I _ pr = t
Substitute the given values Since the interest rate is 5 r = 005$600 __
$1000 middot 005 = t
12 = t
So the length of time for the loan is 12 years
B Determine the interest rate for a $2000 loan that will be paid off in 4 years with interest totaling $640 In order to find the interest rate solve the formula for r
I = prt
I _ = prt _
_ = r
Now substitute the values and simplify
__
( ) ( ) = r
008 = r
So the interest rate is per year
Your Turn
3 The formula y = mx + b is the slope-intercept form of the equation of a line Solve the equation for m
Module 2 69 Lesson 3
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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oug
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bull Online Homeworkbull Hints and Helpbull Extra Practice
Solve for the indicated variable in each mathematical formula
1 C = 2πr for r 2 A = 1 __ 2 bh for b 3 y = mx + b for x
4 A = 1 __ 2 (a + b)h for h 5 V = πr2h for h 6 SA = 2πr2 + 2πrh for h
Solve for the indicated variable in each scientific formula
7 d = rt for t 8 PV = nRT for T
9 A = FV - OV _______ T for OV 10 C = Wtc _ 1000 for W
Evaluate Homework and Practice
Elaborate
4 Discussion What could be a reason for isolating a variable in a literal equation
5 Describe a situation in which a formula could be used more easily if it were rearranged Include the formula in your description
6 Essential Question Check-In How do you isolate a variable
Module 2 70 Lesson 3
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cean
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orb
is
Solve for the indicated variable in each literal equation
11 2p + 5r = q for p 12 -10 = xy + z for x 13 a __ b = c for b
14 h - 4 _ j = k for j 15 x __ 5 - g = a for x 16 5p + 9c = p for c
17 2 __ 5 (z + 1) = y for z 18 g (h + 2 __ 3 ) = 1 for h 19 a(n - 3) + 8 = bn for n
20 Which is a possible way to rewrite the equation y = 3x + 3b to solve for b
A b = y - 3x
_ 3 C b = y - 3
_____ 3x
B b = 3(y - 3x) D b = x(y - 3)
21 Sports To find a baseball pitcherrsquos earned run average (ERA) you can use the formula Ei = 9r in which E represents ERA i represents the number of innings pitched and r represents the number of earned runs allowed Solve the equation for E What is a pitcherrsquos ERA if he allows 5 earned runs in 18 innings pitched
22 Meteorology For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Solve the equation for a If the atmospheric temperature is -655 ∘F and the ground temperature is 57 ∘F what is the altitude
Module 2 71 Lesson 3
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oug
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Rand
y D
uch
aineA
lamy
HOT Focus on Higher Order Thinking
23 Explain the Error A student was asked to use the formula for the perimeter of a rectangle P = 2ℓ + 2w to solve for ℓ The student came up with an answer P - 2w = 2ℓ What error did the student make Explain Then solve for ℓ
24 Multi-Step The formula c = 5p + 215 relates c the total cost in dollars of hosting a birthday party at a skating rink to p the number of people attending If Alliersquos parents are willing to spend $300 for a party how many people can attend
25 Multi-Step The formula for the area of a triangle is A = 1 __ 2 bh in which b represents the length of thebase and h represents the height If a triangle has an area of 192 mm2 and the height is 12 mm what is the measure of the base
Lesson Performance TaskThe following table shows the average low temperatures in Fahrenheit for the city of Boston for several months during the year The formula F = 9 __ 5 C + 32 allows you to determine the temperature in Fahrenheit when given the temperature in Celsius
MonthTemperature in
FahrenheitTemperature in
Celsius
January 22deg
April 41deg
July 65deg
October 47deg
December 28deg
a Use the information given to determine the average low temperatures in Celsius
b Would it ever be possible for the temperature in Celsius to have a greater value than the temperature in Fahrenheit Explain why or why not
Module 2 72 Lesson 3
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Name Class Date
Resource Locker
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oug
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Mif
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Har
cour
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pan
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mag
e cr
edit
s copy
Patr
ick
Lan
eSo
mos
Imag
esC
orb
is
Explore Creating Inequalities from Verbal DescriptionsAn inequality is a statement that compares two expressions that are not strictly equal by using one of the following inequality signs
Symbol Meaning
lt is less than
le is less than or equal to
gt is greater than
ge is greater than or equal to
ne is not equal to
You have probably seen a sign at an amusement park saying something like ldquoYou must be at least 48 inches tall to ride this riderdquo This statement could be written as h ge 48 in where h represents the height of a person allowed to ride
Nora is planning a birthday party for her little sister Colleen Norarsquos budget will allow her to spend no more than $50 for party supplies Eight children including Colleen will attend the party and Nora wants to determine how much she could spend on party favors for each child She will also purchase a cake for $10 Write an inequality that represents the situation and find possible solutions
A First let c represent the cost of a party favor for each child Write an expression for the total cost of the party as a function of c
c +
B Which inequality symbol should be used to represent the phrase ldquono more thanrdquo
C Write the inequality that represents Norarsquos budget goal
8c + 10 le
D Suppose Nora finds party favors that cost $4 each Use a value of 4 for c and check to see if this inequality is true
8 middot 4 + 10 le 50
le 50
Module 2 73 Lesson 4
24 Creating and Solving Inequalities
Essential Question How do you write and solve an inequality that represents a real-world situation
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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pany
Is the inequality true
Could Nora buy $6 party favors for all of her guests without going over budget
Reflect
1 Why does an inequality represent Norarsquos budget calculation better than an equation
2 The solution set of an inequality consists of all values that make the statement true Describe the whole dollar amounts that are in the solution set for this situation
Explain 1 Creating and Solving Inequalities Involving the Distributive Property
You may need to use the Distributive Property before you can solve an inequality
Distributive Property If a b and c are real numbers then a(b + c) = ab + ac
The inequality sign must be reversed when multiplying or dividing both sides of an inequality by a negative number
Example 1
A Trina is buying 12 shirts for the drama club She will choose a style for the blank shirts and then pay an additional charge of $275 for each shirt to have the club logo If Trina cannot spend more than $99 how much can she spend on each blank shirt Write and solve an inequality to find the possible cost of each blank shirt
Let s represent the cost of each blank shirt
Write an inequality to represent the situation 12(s + 275) le 99
Use the Distributive Property 12s + 33 le 99
Subtraction Property of Inequality 12s + 33 - 33 le 99 - 33
Simplify 12s le 66
Division Property of Inequality 12s ___ 12 le 66 __ 12
Simplify s le 55
Module 2 74 Lesson 4
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oug
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cour
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pan
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Check your answer
Since s le 55 check a smaller number 12(5 + 275) le 99
Trina can order blank shirts that cost $550 or less 93 le 99 true
B Sergio needs to buy gifts for 8 friends He wants to give the same gift to all his friends and he plans to have the gifts wrapped for an additional charge of $150 each If Sergio spends at least $70 he will receive free shipping on his order Write and solve an inequality to determine how much Sergio needs to spend on each gift in order to receive free shipping
Let g be the cost of one gift
Write an inequality to represent the situation ( g + ) ge 70
Use the Distributive Property g + ge 70
Subtraction Property of Inequality g + 12 - ge 70 -
Simplify 8g ge
Division Property of Inequality 8g _
ge 58 _
Simplify g ge
Check your answer
Since g ge 725 check a larger number 8(8 + 150) ge 70
Sergio must spend at least on each gift ge 70
Reflect
3 Discussion Why is the first step in solving the inequality to use the Distributive Property instead of working inside the parentheses
Your Turn
4 Zachary is planning to send a video game to each of his two brothers If he buys the same game for both brothers and pays $475 to ship each game how much can he spend on each game without spending more than $100 Write and solve an inequality for this situation
Solve each inequality
5 4 _ 3 (6x + 9) lt 4 6 -2 ( 1 _ 4 x + 2 ) ge 5
Module 2 75 Lesson 4
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oug
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Explain 2 Creating and Solving Inequalities with Variables on Both Sides
Some inequalities have variable terms on both sides of the inequality symbol You can solve these inequalities the same way you solved equations with variables on both sides Use the properties of inequality to collect all the variable terms on one side and all the constant terms on the other side
Example 2
A The Daily Info charges a fee of $650 plus $80 per week to run an ad The Peoplersquos Paper charges $145 per week For how many weeks must an ad run for the total cost at the Daily Info to be less expensive than the cost at the Peoplersquos Paper Let w be the number of weeks the ad runs in the paper
Write an inequality to represent the situation 650 + 80w lt 145w
Subtraction Property of Inequality 650 + 80w - 80w lt 145w - 80w
Simplify 650 lt 65w
Division Property of Inequality 650 _ 65 lt 65w _ 65
Simplify 10 lt w
The total cost at the Daily Info is less than the cost at the Peoplersquos Paper if the ad runs for more than 10 weeks
B The Home Cleaning Company charges $312 to power-wash the siding of a house plus $12 for each window Power Clean charges $36 per window and the price includes power-washing the siding How many windows must a house have to make the total cost from The Home Cleaning Company less expensive than Power Clean Let w be the number of windows
Write an inequality to represent the situation +12w lt 36w
Subtraction Property of Inequality 312 + 12w - lt 36w -
Simplify 312 lt
Division Property of Inequality 312 _ lt 24w _
Simplify lt w
A house must have more than 13 windows for The Home Cleaning Company to be less expensive than Power Clean
Reflect
7 How would the final inequality change if you divided by ndash24 in the next to last step
Your Turn
8 The school band will sell pizzas to raise money for new uniforms The supplier charges $100 plus $4 per pizza The band members sell the pizzas for $7 each Write and solve an inequality to find how many pizzas the band members will have to sell to make a profit
Module 2 76 Lesson 4
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Elaborate
9 Which inequality symbol would you use to represent the following words or phrases Can you come up with more examples
a at most b farther than c younger than d up to
10 Discussion How are the steps to solving an inequality similar to those for solving an equation How are they different
11 Essential Question Check-In How can you write an inequality that represents a real-world situation
Write an inequality that represents the description and then solve
1 Max has more than 5 carrots (number of carrots Max has = c)
2 Brigitte is shorter than 5 feet (Brigittersquos height = h)
3 Twice a number (x) is less than 10 4 Six more than five times a number (x) is at least twenty-one
5 Dave has $15 to spend on an $8 book and two birthday cards (c) for his friends How much can he spend on each card if he buys the same card for each friend
6 Toni can carry up to 18 lb in her backpack Her lunch weighs 1 lb her gym clothes weigh 2 lb and her books (b) weigh 3 lb each How many books can she carry in her backpack
Evaluate Homework and Practice
bull Online Homeworkbull Hints and Helpbull Extra Practice
Module 2 77 Lesson 4
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Solve each inequality
7 3 (x - 2) gt -3 8 5 + 5 (x + 4) le 20 9 3 + 1 _ 2 (3 - x) lt -7
10 3 (x + 6) - 2 (x + 2) ge 10 11 5 (3 - x) -4 (2 - 3x) gt 2 12 1 _ 2 (4x - 2) - 2 _ 3 (6x + 9) le 4
13 x + 1 gt -5 (7 - 2x) 14 5 _ 3 (6x + 3) le 2x - 7
15 2x le - 2 __ 3 (4x + 4) 16 1 __ 2 (-2x - 10) gt 3 (4 - 6x)
17 -5 - 3x ge 2 (10 + 2x) + 3 18 -3 (9x + 20) ge 15x - 20
19 8 ( 1 _ 4 x - 3) + 24 lt 4 ( x + 5 ) 20 6x - 2 (x + 2) gt 2 - 3 (x + 3)
Module 2 78 Lesson 4
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21 Physics A crane cable can support a maximum load of 15000 kg If a bucket has a mass of 2000 kg and gravel has a mass of 1500 kg for every cubic meter how many cubic meters of gravel (g) can be safely lifted by the crane
22 Find the solution set of each inequality below and then determine which inequalities have the same solution set as 1 _ 3 ( -5x - 3 ) lt 14
a 1 _ 3 (5x + 3) gt -14 b 2 _ 5 (10x + 20) gt 44
c - 2 _ 5 (10x + 20) lt -44 d - 1 _ 3 (5x + 3) lt 14
e 2 _ 5 (10x - 20) gt -44 f 1 _ 3 (5x + 3) lt -14
HOT Focus on Higher Order Thinking
23 Explain the Error Sven is trying to find the maximum amount of time he can spend practicing the five scales of piano music he is supposed to be working on He has 60 minutes to practice piano and would like to spend at least 35 minutes playing songs instead of practicing scales So Sven sets up the following inequality where t is the number of minutes he spends on each scale and solves it
60 - 5t le 35-5t le -25
t ge 5
Sven has concluded that he should spend 5 minutes or more on each scale Is this correct If not what mistake did he make Then solve for the correct answer
Module 2 79 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
24 Critical Thinking Anika wants to determine the maximum number of tulip bulbs (t) she can purchase if each bulb costs $150 She will also need to purchase separate pots for each bulb at $125 each and a bag of potting soil for $1000 Set up an inequality to determine how many tulip bulbs Anika can purchase without spending more than $2000 and solve it Can Anika buy exactly enough bulbs and pots to spend the full $2000 Explain Can you think of a better inequality to describe the answer
25 Geometry The area of the triangle shown is no more than 10 square inches
a Write an inequality that can be used to find x
b Solve the inequality from part a c What is the maximum height of the triangle
Lesson Performance TaskWhen planning an airplane route the trip planner must be careful to consider the range the aircraft can travel and the availability of airports to stop and refuel
A large commercial jet airplane burns approximately 5 gallons of fuel per mile flown plus about 8500 gallons of fuel per trip to reach cruising altitude With a useable fuel capacity of 50000 gallons (there is additional fuel reserved for emergencies) describe the acceptable distance for which an airline could establish a non-stop flight
For flights originating from Chicago determine which cities could be safely reached by a non-stop flight
City Distance from Chicago (miles)
Bangalore India 8530
Jakarta Indonesia 9810
Johannesburg South Africa 8680
Moscow Russia 4970
Paris France 4130
Perth Australia 10970
Tokyo Japan 6300
copy H
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eva O
lesiaShutterstock
(2x - 3) in
4 in
Module 2 80 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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Name Class Date
Resource Locker
Explore Truth Tables and Compound StatementsA compound statement is formed by combining two or more simple statements A compound statement can be true or false A compound statement involving AND is true when both simple statements are true A compound statement involving OR is true when either one simple statement or both are true
A Complete the truth table
P QP
True or FalseQ
True or FalseP AND Q
True or False
A dog is a mammal Red is a color
A dog is a mammal Red is not a color
A dog is a fish Red is a color
A dog is a fish Red is not a color
B P AND Q is true when
C Complete the truth table
P QP
True or FalseQ
True or FalseP OR Q
True or False
1 is an odd number 2 is an even number
1 is an odd number 2 is an odd number
1 is an even number 2 is an even number
1 is an even number 2 is an odd number
D P OR Q is true when
Reflect
1 Give two simple statements P and Q for which P AND Q is false and P OR Q is true
Module 2 81 Lesson 5
25 Creating and Solving Compound Inequalities
Essential Question How can you solve a compound inequality and graph the solution set
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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Explain 1 Solving Compound Inequalities Involving ANDCombining two or more simple inequalities forms a compound inequality The graph of a compound inequality involving AND is the intersection or the overlapping region of the simple inequality graphs
Compound Inequalities AND
Words Algebra Graph
All real numbers greater than 2AND less than 6
x gt 2 AND x lt 62 lt x lt 6
All real numbers greater than or equal to 2 AND less than or equal to 6
x ge 2 AND x le 62 le x le 6
Example 1 Solve each compound inequality and graph the solutions
A 4 le x + 2 le 8
4 le x + 2 AND x + 2 le 8 Write the compound inequality using AND
4 - 2 le x + 2 - 2 x + 2 - 2 le 8 - 2 Subtract 2 from both sides of each simple inequality
2 le x x le 6 Simplify
Graph 2 le x
Graph x le 6
Graph the intersection by finding where the two graphs overlap
B -5 le 2x + 3 lt 9
-5 - le 2x + 3 - lt 9 - Subtract from each part of the inequality
le 2x lt Simplify
-8 _ le 2x _ lt 6 _ Divide each part of the inequality by
le x lt Simplify
Graph -4 le x
Graph x lt 3
Graph the intersection by finding where the two graphs overlap -1 0 1 2 3 4 5-5-4 -3 -2
0 2 4 6 8 10 12-8-6-4 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 82 Lesson 5
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Reflect
2 Discussion Explain why 2 le x le 6 can be considered the short method for writing the AND compound inequality x ge 2 AND x le 6
YourTurn
Solve each compound inequality and graph the solutions
3 -2 lt x - 3 lt 5
4 -10 lt 3x + 2 le 8
Explain 2 Solving Compound Inequalities Involving ORThe graph of a compound inequality involving OR is the union or the combined region of the simple inequality graphs
Compound Inequalities OR
Words Algebra Graph
All real numbers less than 2OR greater than 6
x lt 2 OR x gt 6
All real numbers less than or equal to 2OR greater than or equal to 6
x le 2 OR x ge 6
-1 0 1 2 3 4 5-5-4 -3 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 83 Lesson 5
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Example 2 Solve each compound inequality and graph the solutions
A -4 + x gt 1 OR -4 + x lt -3
-4 + x gt 1 OR -4 + x lt -3 Write the compound inequality using OR
-4 + 4 + x gt 1 + 4 -4 + 4 + x lt -3 + 4 Add 4 to both sides of each simple inequality
x gt 5 x lt 1 Simplify
Graph x gt 5
Graph x lt 1
Graph the union by combining the graphs
B 2x le 6 OR 3x gt 12
2x le 6 OR 3x gt 12 Write the compound inequality using OR
2x _ le 6 _ OR 3x _ gt 12 _ Divide the first simple inequality by
x le OR x gt
Graph x le 3
Graph x gt 4
Graph the union by combining the graphs
Reflect
5 Critical Thinking What kind of compound inequality has no solution
Divide the second simple inequality by
Simplify
0 1 2 3 4 5 6-4 -3 -2 -1
-0 1 2 3 4 5 6-4 -3 -2 -1
Module 2 84 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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Com
pan
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Your Turn
Solve each compound inequality and graph the solutions
6 x - 5 ge -2 OR x -5 le -6
7 4x -1 lt 15 OR 8x ge 48
Explain 3 Creating Compound Inequalities From GraphsGiven a number line graph with a solution set graphed you can create a compound inequality to fit the graph
Example 3 Write the compound inequality shown by each graph
A
The shaded portion of the graph is not between two values so the compound inequality involves OR
On the left the graph shows an arrow pointing left from -1 and a solid circle so use le
The inequality is x le -1
On the right the graph shows an arrow pointing right from 7 and a solid circle so use ge
The inequality is x ge 7
The compound inequality is x le -1 OR x ge 7
B
The graph is shaded between the values and so the compound inequality involves AND
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The compound inequality is
-1 0 1 2 3 4 5-5-4 -3 -2
4 5 6 7 8 9 100 1 2 3
2 3 4 5 6 7 8-2 -1 0 1
10 2 3 4 5 6 7 8 9-1
Module 2 85 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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Reflect
8 What is a short method to write the compound inequality x ge 0 AND x lt 6
Your Turn
Write the compound inequality shown by each graph
9
10
Explain 4 Expressing Acceptable Levels with Compound Inequalities
You can express quality-controls levels in real-world problems using compound inequalities
Example 4 Write a compound inequality to represent the indicated quality-control level and graph the solutions
A The recommended pH level for swimming pool water is between 72 and 76 inclusive
Let p be the pH level of swimming pool water
72 is less than or equal to pH level is less than or equal to 76
72 le p le 76
The compound inequality is 72 le p le 76
Graph the solutions
0-10 -8-9 -7-6 -5-4 -3 -2 -1
71 72 73 74 75 76 77 78 79 8070
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 86 Lesson 5
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B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
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arcourt Publishin
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bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
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Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
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oug
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Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
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oug
hton
Mif
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Har
cour
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Com
pan
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mag
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bik
erid
erlo
nd
onS
hutt
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ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
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oug
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The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
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oug
hton Mifflin H
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age C
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igital
Vision
Getty Im
ages
2 Could you write a different equation to describe the situation Explain your reasoning
Explain 1 Creating and Solving Equations Involving the Distributive Property
When you create an equation to model a real-world problem your equation may involve the Distributive Property When you solve a real-world problem you should always check that your answer makes sense
Example 1 Write and solve an equation to solve each problem
A Aaron and Alice are bowling Alicersquos score is twice the difference of Aaronrsquos score and 5 The sum of their scores is 320 Find each studentrsquos bowling score
Write a verbal description of the basic situation
The sum of Aaronrsquos score and Alicersquos score is 320
Choose a variable for the unknown quantity and write an equation to model the detailed situation
Let a represent Aaronrsquos score Then 2 (a - 5) represents Alicersquos score
a + 2 (a - 5) = 320
Solve the equation for a
a + 2 (a - 5) = 320
a + 2a - 10 = 320 Distributive Property
3a - 10 = 320
3a - 10 + 10 = 320 + 10 Addition Property of Equality
3a = 330
3a _ 3 = 330 _ 3 Division Property of Equality
a = 110
So Aaronrsquos score is 110 and Alicersquos score is 2 (a - 5) = 2 (110 - 5) = 2 (105) = 210
Check that the answer makes sense
110 + 210 = 320 so the answer makes sense
B Mari Carlos and Amanda collect stamps Carlos has five more stamps than Mari and Amanda has three times as many stamps as Carlos Altogether they have 100 stamps Find the number of stamps each person has
Write a verbal description of the basic situation
Module 2 56 Lesson 2
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oug
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cour
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pan
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Choose a variable for the unknown quantity and write an equation to model the detailed situation
Let s represent the number of stamps Mari has Then Carlos has stamps
and Amanda has stamps
s + + 3 ( ) =
Solve the equation for s
s + + 3 ( ) =
s + s + 5 + 3s + = Distributive Property
+ = Combine like terms
s = Subtraction Property of Equality
s = Division Property of Equality
So Mari has stamps Carlos has stamps and Amanda
has stamps
Check that the answer makes sense
+ + = the answer makes sense
=
Reflect
3 Would a fractional answer make sense in this situation
4 Discussion What might it mean if a check revealed that the answer to a real-world problem did not make sense
Module 2 57 Lesson 2
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oug
hton Mifflin H
arcourt Publishin
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pany
Your Turn
Write and solve an equation to solve the problem
5 A rectangular garden is fenced on all sides with 256 feet of fencing The garden is 8 feet longer than it is wide Find the length and width of the garden
Explain 2 Creating and Solving Equations with Variables on Both Sides
In some equations variables appear on both sides You can use the properties of equality to collect the variable terms so that they all appear on one side of the equation
Example 2 Write and solve an equation to solve each problem
A Janine has job offers at two companies One company offers a starting salary of $28000 with a raise of $3000 each year The other company offers a starting salary of $36000 with a raise of $2000 each year In how many years would Janinersquos salary be the same with both companies What will the salary be
Write a verbal description of the basic situation
Let n represent the number of years it takes for the salaries to be equal
Base Salary A plus $3000 per year raise = Base Salary B + $2000 per year raise
28000 + 3000n = 36000 + 2000n
28000 + 3000n - 2000n = 36000 + 2000n - 2000n Subtraction Property of Equality
28000 + 1000n = 36000 Combine like terms
28000 + 1000n - 28000 = 36000 - 28000 Subtraction Property of Equality
1000n = 8000 1000n _ 1000 = 8000 _ 1000 Division Property of Equality
n = 8
28000 + 3000 (8) = 36000 + 2000 (8)
52000 = 52000
In 8 years the salaries offered by both companies will be $52000
(w + 8) feet
w feet
Module 2 58 Lesson 2
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pan
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B One moving company charges $800 plus $16 per hour Another moving company charges $720 plus $21 per hour At what number of hours will the charge by both companies be the same What is the charge
Write a verbal description of the basic situation Let t represent the number of hours that the move takes
Moving Charge A plus $16 per hour = Moving Charge B plus $21 per hour
800 + t = 720 + t
800 + t - t = 720 + t - t Subtraction Property of Equality
800 = 720 + t
800 - 720 = 720 + t - 720 Subtraction Property of Equality
= t
_ = t _
Division Property of Equality
t =
The charges are the same for a job that takes hours
Substitute the value 16 in the original equation
800 + 16t = 720 + 21t
800 + 16 ( ) = 720 + 21 ( ) 800 + = 720 +
=
After hours the moving charge for both companies will be
Reflect
6 Suppose you collected the variable terms on the other side of the equal sign to solve the equation Would that affect the solution
Module 2 59 Lesson 2
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oug
hton Mifflin H
arcourt Publishin
g Com
pany
Your Turn
Write and solve an equation to solve each problem7 Claire bought just enough fencing to enclose either a
rectangular garden or a triangular garden as shown The two gardens have the same perimeter How many feet of fencing did she buy
8 A veterinarian is changing the diets of two animals Simba and Cuddles Simba currently consumes 1200 Calories per day That number will increase by 100 Calories each day Cuddles currently consumes 3230 Calories a day That number will decrease by 190 Calories each day The patterns will continue until both animals are consuming the same number of Calories each day In how many days will that be How many Calories will each animal be consuming each day then
Explain 3 Constructing Equations from an Organized TableYou can use a table to organize information and see relationships
Example 3 Construct and solve an equation to solve the problem
Kim works 4 hours more each day than Jill does and Jack works 2 hours less each day than Jill does Over 2 days the number of hours Kim works is equal to the difference of 4 times the number of hours Jack works and the number of hours Jill works How many hours does each person work each day
Analyze Information
Identify the important information
bull Kim works hours more per day than Jill does
bull Jack works hours less per day than Jill does
Formulate a Plan
Make a table using the information given Let x be the number of hours Jill works in one day
Hours Worked Per Day Hours Worked Over 2 Days
Kim
Jill
Jack
Over 2 days the number of hours Kim works is equal to the difference of 4 times the number of hours Jack works and the number of hours Jill works
(3x - 3)(x - 3)
(2x - 1) (2x - 1)
2x
Module 2 60 Lesson 2
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Solve
2 (x + 4) = 4 2 (x - 2) - 2x
2 (x + 4) = (x - 2) - 2x Simplify
2x + = 8x - - 2x Distributive Property
2x + 8 = x - 16
2x + 8 + = 6x - 16 + Addition Property of Equality
2x + = 6x
2x + 24 - x = 6x - x Subtraction Property of Equality
24 = x
24 _ = x _ Division Property of Equality
= x
Jill works hours per day Kim works hours per day and Jack works
hours per day
Justify and Evaluate
Substitute x = 6 into the original equation
2 (6 + 4) = 4 2 (6 - 2) - 2x
2 ( ) = 8 ( ) - 2 ( ) =
Your Turn
Write and solve an equation to solve the problem
9 Lisa is 10 centimeters taller than her friend Ian Ian is 14 centimeters taller than Jim Every month their heights increase by 2 centimeters In 7 months the sum of Ianrsquos and Jimrsquos heights will be 170 centimeters more than Lisarsquos height How tall is Ian now
Height now Height after 7 months
Module 2 61 Lesson 2
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Elaborate
10 How can you use properties to solve equations with variables on both sides
11 How is a table helpful when constructing equations
12 When solving a real-world problem to find a personrsquos age would a negative solution make sense Explain
13 Essential Question Check-In How do you write an equation to represent a real-world situation
bull Online Homeworkbull Hints and Helpbull Extra Practice
Write an equation for each description
1 The sum of 14 and a number is equal to 17 2 A number increased by 10 is 114
3 The difference between a number and 12 is 20 4 Ten times the sum of half a number and 6 is 8
5 Two-thirds a number plus 4 is 7 6 Tanmayi wants to raise $175 for a school fundraiser She has raised $120 so far How much more does she need to reach her goal
7 Hector is visiting a cousin who lives 350 miles away He has driven 90 miles How many more miles does he need to drive to reach his cousinrsquos home
8 The length of a rectangle is twice its width The perimeter of the rectangle is 126 feet
Evaluate Homework and Practice
Module 2 62 Lesson 2
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cour
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pan
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mag
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(t)copy
Pete
r K
imS
hutt
erst
ock
Write and solve an equation for each situation
9 In one baseball season Peter hit twice the difference of the number of home runs Alice hit and 6 Altogether they hit 18 home runs How many home runs did each player hit that season
10 The perimeter of a parallelogram is 72 meters The width of the parallelogram is 4 meters less than its length Find the length and the width of the parallelogram
11 One month Ruby worked 6 hours more than Isaac and Svetlana worked 4 times as many hours as Ruby Together they worked 126 hours Find the number of hours each person worked
12 In one day Annie traveled 5 times the sum of the number of hours Brian traveled and 2 Together they traveled 20 hours Find the number of hours each person traveled
13 Xian and his cousin Kai both collect stamps Xian has 56 stamps and Kai has 80 stamps The boys recently joined different stamp-collecting clubs Xianrsquos club will send him 12 new stamps per month Kairsquos club will send him 8 new stamps per month After how many months will Xian and Kai have the same number of stamps How many stamps will each have
14 Kenya plans to make a down payment plus monthly payments in order to buy a motorcycle At one dealer she would pay $2500 down and $150 each month At another dealer she would pay $3000 down and $125 each month After how many months would the total amount paid be the same for both dealers What would that amount be
ℓ meters
(ℓ - 4) meters
Module 2 63 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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arcourt Publishin
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15 Community Gym charges a $50 membership fee and a $55 monthly fee Workout Gym charges a $200 membership fee and a $45 monthly fee After how many months will the total amount of money paid to both gyms be the same What will the amount be
16 Tina is saving to buy a notebook computer She has two options The first option is to put $200 away initially and save $10 every month The second option is to put $100 away initially and save $30 every month After how many months would Tina save the same amount using either option How much would she save with either option
Use the table to answer each question
Starting Salary Yearly Salary Increase
Company A $24000 $3000
Company B $30000 $2400
Company C $36000 $2000
17 After how many years are the salaries offered by Company A and Company B the same
18 After how many years are the salaries offered by Company B and Company C the same
19 Paul started work at Company B ten years ago at the salary shown in the table At the same time Sharla started at Company C at the salary shown in the table Who earned more during the last year How much more
20 Georgersquos page contains twice as many typed words as Billrsquos page and Billrsquos page contains 50 fewer words than Charliersquos page If each person can type 60 words per minute after one minute the difference between twice the number of words on Billrsquos page and the number of words on Charliersquos page is 210 How many words did Billrsquos page contain initially Use a table to organize the information
Initial number of words
Total number of words after one minute
Module 2 64 Lesson 2
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oug
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Mif
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Har
cour
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lishi
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Com
pan
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21 Geometry Sammie bought just enough fencing to border either a rectangular plot or a square plot as shown The perimeters of the plots are the same How many meters of fencing did she buy
HOT Focus on Higher Order Thinking
22 Justify Reasoning Suppose you want to solve the equation 2a + b = 2a where a and b are nonzero real numbers Describe the solution to this equation Justify your description
23 Multi-step A patio in the shape of a rectangle is fenced on all sides with 134 feet of fencing The patio is 5 feet less wide than it is long
a What information can be used to solve the problem How can you find the information
b Describe how to find the area of the patio What is the area of the patio
24 Explain the Error Kevin and Brittany write an equation to represent the following relationship and both students solve their equation Who found the correct equation and solution Why is the other person incorrect
5 times the difference of a number and 20 is the same as half the sum of 4 more than 4 times a number
Kevin Brittany
5 (x - 20) = 1 _ 2 (4x + 4) 5 (20 + x) = 1 _ 2 (4x + 4)
5x - 100 = 2x + 2 100 - 5x = 2x + 2
3x - 100 = 2 100 - 7x = 2
3x = 102 -7x = -98
x = 34 x = 14
(3x + 2) meters
(x + 2) meters
(x + 2) meters
(x - 1) meters
ℓ feet
(ℓ - 5) feet
Module 2 65 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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arcourt Publishin
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pany
25 What If Alexa and Zack are solving the following problem
The number of miles on Car A is 50 miles more than the number of miles on Car B and the number of miles on Car B is 30 miles more than the number of miles on Car C All the cars travel 50 miles in 1 hour After 1 hour twice the number of miles on Car A is 70 miles less than 3 times the number of miles on Car C How many miles were there on Car B initially
Alexa assumes there are m miles on Car B Zack assumes there are m miles on Car C Will Zackrsquos answer be the same as Alexarsquos answer Explain
Lesson Performance Task
Stacy Oliver and Jivesh each plan to put a certain amount of money into their savings accounts that earn simple interest of 6 per year Stacy puts $550 more than Jivesh and Oliver puts in 2 times as much as Jivesh After a year the amount in Stacyrsquos account is 2 times the sum of $212 and the amount in Oliverrsquos account How much does each person initially put into his or her account Who had the most money in his or her account after a year Who had the least Explain
Zackrsquos Table Initial Miles
Miles after One Hour
Alexarsquos Table Initial Miles
Miles after One Hour
Amount in Account Initially Amount in Account after One Year
Module 2 66 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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Mif
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Har
cour
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lishi
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pan
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Name Class Date
Resource Locker
Explore Rearranging Mathematical FormulasLiteral Equations are equations that contain two or more variables There are many literal equations in the form of math science and engineering formulas These formulas may seem like they can only be solved for the variable that is isolated on one side of the formula By using inverse operations and the properties of equality a formula can be rearranged so any variable in the formula can be isolated It is no different than how equations are solved by using inverse operations and the properties of equality
How can you solve the equation 42 = 6x
A42 _ = 6x _ What is the reason for dividing
Why divide by
= x By rearranging the equation x was isolated and the solution was found
The mathematical formula for the volume of a rectangular prism B = Vh or V = ℓwh is a literal equation V represents volume ℓ represents length w represents width and h represents height Using inverse operations the formula can be rearranged to solve for any one of the variables that might be unknown Like solving for x a formula can be rearranged to isolate a variable
B In the formula V = ℓwh the variable h needs to be isolated
The operation of is used in the formula The inverse
operation should be used
to isolate
C V _____ = ℓwh _____
V _ =
The formula rearranged in this way can easily produce the height of the rectangular prism when the volume length and width are known
Reflect
1 Using the formula for a rectangular prism rewrite the formula to solve for ℓ
ℓw
h
Module 2 67 Lesson 3
23 Solving for a VariableEssential Question How do you rewrite formulas and literal equations
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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arcourt Publishin
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age C
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Photo
grap
hyAurora Ph
otosCorb
is
Explain 1 Rearranging Scientific FormulasUse inverse operations to isolate the unknown variable in a scientific formula
The formula for density is D = m __ V Lead has a very high density of 11340 kg m 3 Plastic foam has a very low density of 75 kg m 3 The formula for density can be rearranged to solve for V volume or m mass
Example 1
A A sinker on a fishing line is made of lead and has a volume of 0000015 m 3 What is the mass of the sinker
The density formula can be rearranged to isolate m the mass The values for volume and density can then be substituted into the formula to find the mass
D = m _ V
DV = ( m _ V ) V DV = m
(11340 kg m 3 ) (0000015 m 3 ) = m
017 kg asymp m
B The design for a life preserver requires 03 kilogram of plastic foam to provide proper buoyancy What is the volume of the plastic foam required
Rearrange the density formula to isolate V
D = m _ V
(D) V = m _ V
DV =
DV _ = m _
V =
Now substitute the given values
V = _
V = m 3
Your Turn
2 For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Determine the altitude in feet when t is -275 ∘F and g is 60 ∘F
Module 2 68 Lesson 3
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
copy H
oug
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Mif
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Har
cour
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Com
pan
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Explain 2 Rearranging Literal EquationsUsing inverse operations to rearrange literal equations can be applied to any formula The interest formula I = prt is another example of a literal equation In the formula I represents interest p the principal or the initial amount to which interest will be applied r the rate at which interest will be paid and t is the time in years
Example 2
A Find the number of years used in the calculation of a $1000 loan at an interest rate of 5 with interest totaling $600
Solve the formula for t
I = prt
I _ pr = prt
_ pr
I _ pr = t
Substitute the given values Since the interest rate is 5 r = 005$600 __
$1000 middot 005 = t
12 = t
So the length of time for the loan is 12 years
B Determine the interest rate for a $2000 loan that will be paid off in 4 years with interest totaling $640 In order to find the interest rate solve the formula for r
I = prt
I _ = prt _
_ = r
Now substitute the values and simplify
__
( ) ( ) = r
008 = r
So the interest rate is per year
Your Turn
3 The formula y = mx + b is the slope-intercept form of the equation of a line Solve the equation for m
Module 2 69 Lesson 3
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
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pany
bull Online Homeworkbull Hints and Helpbull Extra Practice
Solve for the indicated variable in each mathematical formula
1 C = 2πr for r 2 A = 1 __ 2 bh for b 3 y = mx + b for x
4 A = 1 __ 2 (a + b)h for h 5 V = πr2h for h 6 SA = 2πr2 + 2πrh for h
Solve for the indicated variable in each scientific formula
7 d = rt for t 8 PV = nRT for T
9 A = FV - OV _______ T for OV 10 C = Wtc _ 1000 for W
Evaluate Homework and Practice
Elaborate
4 Discussion What could be a reason for isolating a variable in a literal equation
5 Describe a situation in which a formula could be used more easily if it were rearranged Include the formula in your description
6 Essential Question Check-In How do you isolate a variable
Module 2 70 Lesson 3
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is
Solve for the indicated variable in each literal equation
11 2p + 5r = q for p 12 -10 = xy + z for x 13 a __ b = c for b
14 h - 4 _ j = k for j 15 x __ 5 - g = a for x 16 5p + 9c = p for c
17 2 __ 5 (z + 1) = y for z 18 g (h + 2 __ 3 ) = 1 for h 19 a(n - 3) + 8 = bn for n
20 Which is a possible way to rewrite the equation y = 3x + 3b to solve for b
A b = y - 3x
_ 3 C b = y - 3
_____ 3x
B b = 3(y - 3x) D b = x(y - 3)
21 Sports To find a baseball pitcherrsquos earned run average (ERA) you can use the formula Ei = 9r in which E represents ERA i represents the number of innings pitched and r represents the number of earned runs allowed Solve the equation for E What is a pitcherrsquos ERA if he allows 5 earned runs in 18 innings pitched
22 Meteorology For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Solve the equation for a If the atmospheric temperature is -655 ∘F and the ground temperature is 57 ∘F what is the altitude
Module 2 71 Lesson 3
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Rand
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aineA
lamy
HOT Focus on Higher Order Thinking
23 Explain the Error A student was asked to use the formula for the perimeter of a rectangle P = 2ℓ + 2w to solve for ℓ The student came up with an answer P - 2w = 2ℓ What error did the student make Explain Then solve for ℓ
24 Multi-Step The formula c = 5p + 215 relates c the total cost in dollars of hosting a birthday party at a skating rink to p the number of people attending If Alliersquos parents are willing to spend $300 for a party how many people can attend
25 Multi-Step The formula for the area of a triangle is A = 1 __ 2 bh in which b represents the length of thebase and h represents the height If a triangle has an area of 192 mm2 and the height is 12 mm what is the measure of the base
Lesson Performance TaskThe following table shows the average low temperatures in Fahrenheit for the city of Boston for several months during the year The formula F = 9 __ 5 C + 32 allows you to determine the temperature in Fahrenheit when given the temperature in Celsius
MonthTemperature in
FahrenheitTemperature in
Celsius
January 22deg
April 41deg
July 65deg
October 47deg
December 28deg
a Use the information given to determine the average low temperatures in Celsius
b Would it ever be possible for the temperature in Celsius to have a greater value than the temperature in Fahrenheit Explain why or why not
Module 2 72 Lesson 3
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Name Class Date
Resource Locker
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oug
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pan
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e cr
edit
s copy
Patr
ick
Lan
eSo
mos
Imag
esC
orb
is
Explore Creating Inequalities from Verbal DescriptionsAn inequality is a statement that compares two expressions that are not strictly equal by using one of the following inequality signs
Symbol Meaning
lt is less than
le is less than or equal to
gt is greater than
ge is greater than or equal to
ne is not equal to
You have probably seen a sign at an amusement park saying something like ldquoYou must be at least 48 inches tall to ride this riderdquo This statement could be written as h ge 48 in where h represents the height of a person allowed to ride
Nora is planning a birthday party for her little sister Colleen Norarsquos budget will allow her to spend no more than $50 for party supplies Eight children including Colleen will attend the party and Nora wants to determine how much she could spend on party favors for each child She will also purchase a cake for $10 Write an inequality that represents the situation and find possible solutions
A First let c represent the cost of a party favor for each child Write an expression for the total cost of the party as a function of c
c +
B Which inequality symbol should be used to represent the phrase ldquono more thanrdquo
C Write the inequality that represents Norarsquos budget goal
8c + 10 le
D Suppose Nora finds party favors that cost $4 each Use a value of 4 for c and check to see if this inequality is true
8 middot 4 + 10 le 50
le 50
Module 2 73 Lesson 4
24 Creating and Solving Inequalities
Essential Question How do you write and solve an inequality that represents a real-world situation
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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pany
Is the inequality true
Could Nora buy $6 party favors for all of her guests without going over budget
Reflect
1 Why does an inequality represent Norarsquos budget calculation better than an equation
2 The solution set of an inequality consists of all values that make the statement true Describe the whole dollar amounts that are in the solution set for this situation
Explain 1 Creating and Solving Inequalities Involving the Distributive Property
You may need to use the Distributive Property before you can solve an inequality
Distributive Property If a b and c are real numbers then a(b + c) = ab + ac
The inequality sign must be reversed when multiplying or dividing both sides of an inequality by a negative number
Example 1
A Trina is buying 12 shirts for the drama club She will choose a style for the blank shirts and then pay an additional charge of $275 for each shirt to have the club logo If Trina cannot spend more than $99 how much can she spend on each blank shirt Write and solve an inequality to find the possible cost of each blank shirt
Let s represent the cost of each blank shirt
Write an inequality to represent the situation 12(s + 275) le 99
Use the Distributive Property 12s + 33 le 99
Subtraction Property of Inequality 12s + 33 - 33 le 99 - 33
Simplify 12s le 66
Division Property of Inequality 12s ___ 12 le 66 __ 12
Simplify s le 55
Module 2 74 Lesson 4
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Check your answer
Since s le 55 check a smaller number 12(5 + 275) le 99
Trina can order blank shirts that cost $550 or less 93 le 99 true
B Sergio needs to buy gifts for 8 friends He wants to give the same gift to all his friends and he plans to have the gifts wrapped for an additional charge of $150 each If Sergio spends at least $70 he will receive free shipping on his order Write and solve an inequality to determine how much Sergio needs to spend on each gift in order to receive free shipping
Let g be the cost of one gift
Write an inequality to represent the situation ( g + ) ge 70
Use the Distributive Property g + ge 70
Subtraction Property of Inequality g + 12 - ge 70 -
Simplify 8g ge
Division Property of Inequality 8g _
ge 58 _
Simplify g ge
Check your answer
Since g ge 725 check a larger number 8(8 + 150) ge 70
Sergio must spend at least on each gift ge 70
Reflect
3 Discussion Why is the first step in solving the inequality to use the Distributive Property instead of working inside the parentheses
Your Turn
4 Zachary is planning to send a video game to each of his two brothers If he buys the same game for both brothers and pays $475 to ship each game how much can he spend on each game without spending more than $100 Write and solve an inequality for this situation
Solve each inequality
5 4 _ 3 (6x + 9) lt 4 6 -2 ( 1 _ 4 x + 2 ) ge 5
Module 2 75 Lesson 4
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Explain 2 Creating and Solving Inequalities with Variables on Both Sides
Some inequalities have variable terms on both sides of the inequality symbol You can solve these inequalities the same way you solved equations with variables on both sides Use the properties of inequality to collect all the variable terms on one side and all the constant terms on the other side
Example 2
A The Daily Info charges a fee of $650 plus $80 per week to run an ad The Peoplersquos Paper charges $145 per week For how many weeks must an ad run for the total cost at the Daily Info to be less expensive than the cost at the Peoplersquos Paper Let w be the number of weeks the ad runs in the paper
Write an inequality to represent the situation 650 + 80w lt 145w
Subtraction Property of Inequality 650 + 80w - 80w lt 145w - 80w
Simplify 650 lt 65w
Division Property of Inequality 650 _ 65 lt 65w _ 65
Simplify 10 lt w
The total cost at the Daily Info is less than the cost at the Peoplersquos Paper if the ad runs for more than 10 weeks
B The Home Cleaning Company charges $312 to power-wash the siding of a house plus $12 for each window Power Clean charges $36 per window and the price includes power-washing the siding How many windows must a house have to make the total cost from The Home Cleaning Company less expensive than Power Clean Let w be the number of windows
Write an inequality to represent the situation +12w lt 36w
Subtraction Property of Inequality 312 + 12w - lt 36w -
Simplify 312 lt
Division Property of Inequality 312 _ lt 24w _
Simplify lt w
A house must have more than 13 windows for The Home Cleaning Company to be less expensive than Power Clean
Reflect
7 How would the final inequality change if you divided by ndash24 in the next to last step
Your Turn
8 The school band will sell pizzas to raise money for new uniforms The supplier charges $100 plus $4 per pizza The band members sell the pizzas for $7 each Write and solve an inequality to find how many pizzas the band members will have to sell to make a profit
Module 2 76 Lesson 4
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Elaborate
9 Which inequality symbol would you use to represent the following words or phrases Can you come up with more examples
a at most b farther than c younger than d up to
10 Discussion How are the steps to solving an inequality similar to those for solving an equation How are they different
11 Essential Question Check-In How can you write an inequality that represents a real-world situation
Write an inequality that represents the description and then solve
1 Max has more than 5 carrots (number of carrots Max has = c)
2 Brigitte is shorter than 5 feet (Brigittersquos height = h)
3 Twice a number (x) is less than 10 4 Six more than five times a number (x) is at least twenty-one
5 Dave has $15 to spend on an $8 book and two birthday cards (c) for his friends How much can he spend on each card if he buys the same card for each friend
6 Toni can carry up to 18 lb in her backpack Her lunch weighs 1 lb her gym clothes weigh 2 lb and her books (b) weigh 3 lb each How many books can she carry in her backpack
Evaluate Homework and Practice
bull Online Homeworkbull Hints and Helpbull Extra Practice
Module 2 77 Lesson 4
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pany
Solve each inequality
7 3 (x - 2) gt -3 8 5 + 5 (x + 4) le 20 9 3 + 1 _ 2 (3 - x) lt -7
10 3 (x + 6) - 2 (x + 2) ge 10 11 5 (3 - x) -4 (2 - 3x) gt 2 12 1 _ 2 (4x - 2) - 2 _ 3 (6x + 9) le 4
13 x + 1 gt -5 (7 - 2x) 14 5 _ 3 (6x + 3) le 2x - 7
15 2x le - 2 __ 3 (4x + 4) 16 1 __ 2 (-2x - 10) gt 3 (4 - 6x)
17 -5 - 3x ge 2 (10 + 2x) + 3 18 -3 (9x + 20) ge 15x - 20
19 8 ( 1 _ 4 x - 3) + 24 lt 4 ( x + 5 ) 20 6x - 2 (x + 2) gt 2 - 3 (x + 3)
Module 2 78 Lesson 4
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21 Physics A crane cable can support a maximum load of 15000 kg If a bucket has a mass of 2000 kg and gravel has a mass of 1500 kg for every cubic meter how many cubic meters of gravel (g) can be safely lifted by the crane
22 Find the solution set of each inequality below and then determine which inequalities have the same solution set as 1 _ 3 ( -5x - 3 ) lt 14
a 1 _ 3 (5x + 3) gt -14 b 2 _ 5 (10x + 20) gt 44
c - 2 _ 5 (10x + 20) lt -44 d - 1 _ 3 (5x + 3) lt 14
e 2 _ 5 (10x - 20) gt -44 f 1 _ 3 (5x + 3) lt -14
HOT Focus on Higher Order Thinking
23 Explain the Error Sven is trying to find the maximum amount of time he can spend practicing the five scales of piano music he is supposed to be working on He has 60 minutes to practice piano and would like to spend at least 35 minutes playing songs instead of practicing scales So Sven sets up the following inequality where t is the number of minutes he spends on each scale and solves it
60 - 5t le 35-5t le -25
t ge 5
Sven has concluded that he should spend 5 minutes or more on each scale Is this correct If not what mistake did he make Then solve for the correct answer
Module 2 79 Lesson 4
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24 Critical Thinking Anika wants to determine the maximum number of tulip bulbs (t) she can purchase if each bulb costs $150 She will also need to purchase separate pots for each bulb at $125 each and a bag of potting soil for $1000 Set up an inequality to determine how many tulip bulbs Anika can purchase without spending more than $2000 and solve it Can Anika buy exactly enough bulbs and pots to spend the full $2000 Explain Can you think of a better inequality to describe the answer
25 Geometry The area of the triangle shown is no more than 10 square inches
a Write an inequality that can be used to find x
b Solve the inequality from part a c What is the maximum height of the triangle
Lesson Performance TaskWhen planning an airplane route the trip planner must be careful to consider the range the aircraft can travel and the availability of airports to stop and refuel
A large commercial jet airplane burns approximately 5 gallons of fuel per mile flown plus about 8500 gallons of fuel per trip to reach cruising altitude With a useable fuel capacity of 50000 gallons (there is additional fuel reserved for emergencies) describe the acceptable distance for which an airline could establish a non-stop flight
For flights originating from Chicago determine which cities could be safely reached by a non-stop flight
City Distance from Chicago (miles)
Bangalore India 8530
Jakarta Indonesia 9810
Johannesburg South Africa 8680
Moscow Russia 4970
Paris France 4130
Perth Australia 10970
Tokyo Japan 6300
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eva O
lesiaShutterstock
(2x - 3) in
4 in
Module 2 80 Lesson 4
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Name Class Date
Resource Locker
Explore Truth Tables and Compound StatementsA compound statement is formed by combining two or more simple statements A compound statement can be true or false A compound statement involving AND is true when both simple statements are true A compound statement involving OR is true when either one simple statement or both are true
A Complete the truth table
P QP
True or FalseQ
True or FalseP AND Q
True or False
A dog is a mammal Red is a color
A dog is a mammal Red is not a color
A dog is a fish Red is a color
A dog is a fish Red is not a color
B P AND Q is true when
C Complete the truth table
P QP
True or FalseQ
True or FalseP OR Q
True or False
1 is an odd number 2 is an even number
1 is an odd number 2 is an odd number
1 is an even number 2 is an even number
1 is an even number 2 is an odd number
D P OR Q is true when
Reflect
1 Give two simple statements P and Q for which P AND Q is false and P OR Q is true
Module 2 81 Lesson 5
25 Creating and Solving Compound Inequalities
Essential Question How can you solve a compound inequality and graph the solution set
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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Explain 1 Solving Compound Inequalities Involving ANDCombining two or more simple inequalities forms a compound inequality The graph of a compound inequality involving AND is the intersection or the overlapping region of the simple inequality graphs
Compound Inequalities AND
Words Algebra Graph
All real numbers greater than 2AND less than 6
x gt 2 AND x lt 62 lt x lt 6
All real numbers greater than or equal to 2 AND less than or equal to 6
x ge 2 AND x le 62 le x le 6
Example 1 Solve each compound inequality and graph the solutions
A 4 le x + 2 le 8
4 le x + 2 AND x + 2 le 8 Write the compound inequality using AND
4 - 2 le x + 2 - 2 x + 2 - 2 le 8 - 2 Subtract 2 from both sides of each simple inequality
2 le x x le 6 Simplify
Graph 2 le x
Graph x le 6
Graph the intersection by finding where the two graphs overlap
B -5 le 2x + 3 lt 9
-5 - le 2x + 3 - lt 9 - Subtract from each part of the inequality
le 2x lt Simplify
-8 _ le 2x _ lt 6 _ Divide each part of the inequality by
le x lt Simplify
Graph -4 le x
Graph x lt 3
Graph the intersection by finding where the two graphs overlap -1 0 1 2 3 4 5-5-4 -3 -2
0 2 4 6 8 10 12-8-6-4 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 82 Lesson 5
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Reflect
2 Discussion Explain why 2 le x le 6 can be considered the short method for writing the AND compound inequality x ge 2 AND x le 6
YourTurn
Solve each compound inequality and graph the solutions
3 -2 lt x - 3 lt 5
4 -10 lt 3x + 2 le 8
Explain 2 Solving Compound Inequalities Involving ORThe graph of a compound inequality involving OR is the union or the combined region of the simple inequality graphs
Compound Inequalities OR
Words Algebra Graph
All real numbers less than 2OR greater than 6
x lt 2 OR x gt 6
All real numbers less than or equal to 2OR greater than or equal to 6
x le 2 OR x ge 6
-1 0 1 2 3 4 5-5-4 -3 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 83 Lesson 5
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Example 2 Solve each compound inequality and graph the solutions
A -4 + x gt 1 OR -4 + x lt -3
-4 + x gt 1 OR -4 + x lt -3 Write the compound inequality using OR
-4 + 4 + x gt 1 + 4 -4 + 4 + x lt -3 + 4 Add 4 to both sides of each simple inequality
x gt 5 x lt 1 Simplify
Graph x gt 5
Graph x lt 1
Graph the union by combining the graphs
B 2x le 6 OR 3x gt 12
2x le 6 OR 3x gt 12 Write the compound inequality using OR
2x _ le 6 _ OR 3x _ gt 12 _ Divide the first simple inequality by
x le OR x gt
Graph x le 3
Graph x gt 4
Graph the union by combining the graphs
Reflect
5 Critical Thinking What kind of compound inequality has no solution
Divide the second simple inequality by
Simplify
0 1 2 3 4 5 6-4 -3 -2 -1
-0 1 2 3 4 5 6-4 -3 -2 -1
Module 2 84 Lesson 5
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Your Turn
Solve each compound inequality and graph the solutions
6 x - 5 ge -2 OR x -5 le -6
7 4x -1 lt 15 OR 8x ge 48
Explain 3 Creating Compound Inequalities From GraphsGiven a number line graph with a solution set graphed you can create a compound inequality to fit the graph
Example 3 Write the compound inequality shown by each graph
A
The shaded portion of the graph is not between two values so the compound inequality involves OR
On the left the graph shows an arrow pointing left from -1 and a solid circle so use le
The inequality is x le -1
On the right the graph shows an arrow pointing right from 7 and a solid circle so use ge
The inequality is x ge 7
The compound inequality is x le -1 OR x ge 7
B
The graph is shaded between the values and so the compound inequality involves AND
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The compound inequality is
-1 0 1 2 3 4 5-5-4 -3 -2
4 5 6 7 8 9 100 1 2 3
2 3 4 5 6 7 8-2 -1 0 1
10 2 3 4 5 6 7 8 9-1
Module 2 85 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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Reflect
8 What is a short method to write the compound inequality x ge 0 AND x lt 6
Your Turn
Write the compound inequality shown by each graph
9
10
Explain 4 Expressing Acceptable Levels with Compound Inequalities
You can express quality-controls levels in real-world problems using compound inequalities
Example 4 Write a compound inequality to represent the indicated quality-control level and graph the solutions
A The recommended pH level for swimming pool water is between 72 and 76 inclusive
Let p be the pH level of swimming pool water
72 is less than or equal to pH level is less than or equal to 76
72 le p le 76
The compound inequality is 72 le p le 76
Graph the solutions
0-10 -8-9 -7-6 -5-4 -3 -2 -1
71 72 73 74 75 76 77 78 79 8070
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 86 Lesson 5
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B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
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Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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age C
redits copy
Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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Mif
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pan
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mag
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red
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copy
bik
erid
erlo
nd
onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
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arcourt Publishin
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pany
The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
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Choose a variable for the unknown quantity and write an equation to model the detailed situation
Let s represent the number of stamps Mari has Then Carlos has stamps
and Amanda has stamps
s + + 3 ( ) =
Solve the equation for s
s + + 3 ( ) =
s + s + 5 + 3s + = Distributive Property
+ = Combine like terms
s = Subtraction Property of Equality
s = Division Property of Equality
So Mari has stamps Carlos has stamps and Amanda
has stamps
Check that the answer makes sense
+ + = the answer makes sense
=
Reflect
3 Would a fractional answer make sense in this situation
4 Discussion What might it mean if a check revealed that the answer to a real-world problem did not make sense
Module 2 57 Lesson 2
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pany
Your Turn
Write and solve an equation to solve the problem
5 A rectangular garden is fenced on all sides with 256 feet of fencing The garden is 8 feet longer than it is wide Find the length and width of the garden
Explain 2 Creating and Solving Equations with Variables on Both Sides
In some equations variables appear on both sides You can use the properties of equality to collect the variable terms so that they all appear on one side of the equation
Example 2 Write and solve an equation to solve each problem
A Janine has job offers at two companies One company offers a starting salary of $28000 with a raise of $3000 each year The other company offers a starting salary of $36000 with a raise of $2000 each year In how many years would Janinersquos salary be the same with both companies What will the salary be
Write a verbal description of the basic situation
Let n represent the number of years it takes for the salaries to be equal
Base Salary A plus $3000 per year raise = Base Salary B + $2000 per year raise
28000 + 3000n = 36000 + 2000n
28000 + 3000n - 2000n = 36000 + 2000n - 2000n Subtraction Property of Equality
28000 + 1000n = 36000 Combine like terms
28000 + 1000n - 28000 = 36000 - 28000 Subtraction Property of Equality
1000n = 8000 1000n _ 1000 = 8000 _ 1000 Division Property of Equality
n = 8
28000 + 3000 (8) = 36000 + 2000 (8)
52000 = 52000
In 8 years the salaries offered by both companies will be $52000
(w + 8) feet
w feet
Module 2 58 Lesson 2
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Har
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pan
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B One moving company charges $800 plus $16 per hour Another moving company charges $720 plus $21 per hour At what number of hours will the charge by both companies be the same What is the charge
Write a verbal description of the basic situation Let t represent the number of hours that the move takes
Moving Charge A plus $16 per hour = Moving Charge B plus $21 per hour
800 + t = 720 + t
800 + t - t = 720 + t - t Subtraction Property of Equality
800 = 720 + t
800 - 720 = 720 + t - 720 Subtraction Property of Equality
= t
_ = t _
Division Property of Equality
t =
The charges are the same for a job that takes hours
Substitute the value 16 in the original equation
800 + 16t = 720 + 21t
800 + 16 ( ) = 720 + 21 ( ) 800 + = 720 +
=
After hours the moving charge for both companies will be
Reflect
6 Suppose you collected the variable terms on the other side of the equal sign to solve the equation Would that affect the solution
Module 2 59 Lesson 2
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oug
hton Mifflin H
arcourt Publishin
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pany
Your Turn
Write and solve an equation to solve each problem7 Claire bought just enough fencing to enclose either a
rectangular garden or a triangular garden as shown The two gardens have the same perimeter How many feet of fencing did she buy
8 A veterinarian is changing the diets of two animals Simba and Cuddles Simba currently consumes 1200 Calories per day That number will increase by 100 Calories each day Cuddles currently consumes 3230 Calories a day That number will decrease by 190 Calories each day The patterns will continue until both animals are consuming the same number of Calories each day In how many days will that be How many Calories will each animal be consuming each day then
Explain 3 Constructing Equations from an Organized TableYou can use a table to organize information and see relationships
Example 3 Construct and solve an equation to solve the problem
Kim works 4 hours more each day than Jill does and Jack works 2 hours less each day than Jill does Over 2 days the number of hours Kim works is equal to the difference of 4 times the number of hours Jack works and the number of hours Jill works How many hours does each person work each day
Analyze Information
Identify the important information
bull Kim works hours more per day than Jill does
bull Jack works hours less per day than Jill does
Formulate a Plan
Make a table using the information given Let x be the number of hours Jill works in one day
Hours Worked Per Day Hours Worked Over 2 Days
Kim
Jill
Jack
Over 2 days the number of hours Kim works is equal to the difference of 4 times the number of hours Jack works and the number of hours Jill works
(3x - 3)(x - 3)
(2x - 1) (2x - 1)
2x
Module 2 60 Lesson 2
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pan
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Solve
2 (x + 4) = 4 2 (x - 2) - 2x
2 (x + 4) = (x - 2) - 2x Simplify
2x + = 8x - - 2x Distributive Property
2x + 8 = x - 16
2x + 8 + = 6x - 16 + Addition Property of Equality
2x + = 6x
2x + 24 - x = 6x - x Subtraction Property of Equality
24 = x
24 _ = x _ Division Property of Equality
= x
Jill works hours per day Kim works hours per day and Jack works
hours per day
Justify and Evaluate
Substitute x = 6 into the original equation
2 (6 + 4) = 4 2 (6 - 2) - 2x
2 ( ) = 8 ( ) - 2 ( ) =
Your Turn
Write and solve an equation to solve the problem
9 Lisa is 10 centimeters taller than her friend Ian Ian is 14 centimeters taller than Jim Every month their heights increase by 2 centimeters In 7 months the sum of Ianrsquos and Jimrsquos heights will be 170 centimeters more than Lisarsquos height How tall is Ian now
Height now Height after 7 months
Module 2 61 Lesson 2
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pany
Elaborate
10 How can you use properties to solve equations with variables on both sides
11 How is a table helpful when constructing equations
12 When solving a real-world problem to find a personrsquos age would a negative solution make sense Explain
13 Essential Question Check-In How do you write an equation to represent a real-world situation
bull Online Homeworkbull Hints and Helpbull Extra Practice
Write an equation for each description
1 The sum of 14 and a number is equal to 17 2 A number increased by 10 is 114
3 The difference between a number and 12 is 20 4 Ten times the sum of half a number and 6 is 8
5 Two-thirds a number plus 4 is 7 6 Tanmayi wants to raise $175 for a school fundraiser She has raised $120 so far How much more does she need to reach her goal
7 Hector is visiting a cousin who lives 350 miles away He has driven 90 miles How many more miles does he need to drive to reach his cousinrsquos home
8 The length of a rectangle is twice its width The perimeter of the rectangle is 126 feet
Evaluate Homework and Practice
Module 2 62 Lesson 2
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oug
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cour
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pan
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mag
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(t)copy
Pete
r K
imS
hutt
erst
ock
Write and solve an equation for each situation
9 In one baseball season Peter hit twice the difference of the number of home runs Alice hit and 6 Altogether they hit 18 home runs How many home runs did each player hit that season
10 The perimeter of a parallelogram is 72 meters The width of the parallelogram is 4 meters less than its length Find the length and the width of the parallelogram
11 One month Ruby worked 6 hours more than Isaac and Svetlana worked 4 times as many hours as Ruby Together they worked 126 hours Find the number of hours each person worked
12 In one day Annie traveled 5 times the sum of the number of hours Brian traveled and 2 Together they traveled 20 hours Find the number of hours each person traveled
13 Xian and his cousin Kai both collect stamps Xian has 56 stamps and Kai has 80 stamps The boys recently joined different stamp-collecting clubs Xianrsquos club will send him 12 new stamps per month Kairsquos club will send him 8 new stamps per month After how many months will Xian and Kai have the same number of stamps How many stamps will each have
14 Kenya plans to make a down payment plus monthly payments in order to buy a motorcycle At one dealer she would pay $2500 down and $150 each month At another dealer she would pay $3000 down and $125 each month After how many months would the total amount paid be the same for both dealers What would that amount be
ℓ meters
(ℓ - 4) meters
Module 2 63 Lesson 2
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oug
hton Mifflin H
arcourt Publishin
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pany
15 Community Gym charges a $50 membership fee and a $55 monthly fee Workout Gym charges a $200 membership fee and a $45 monthly fee After how many months will the total amount of money paid to both gyms be the same What will the amount be
16 Tina is saving to buy a notebook computer She has two options The first option is to put $200 away initially and save $10 every month The second option is to put $100 away initially and save $30 every month After how many months would Tina save the same amount using either option How much would she save with either option
Use the table to answer each question
Starting Salary Yearly Salary Increase
Company A $24000 $3000
Company B $30000 $2400
Company C $36000 $2000
17 After how many years are the salaries offered by Company A and Company B the same
18 After how many years are the salaries offered by Company B and Company C the same
19 Paul started work at Company B ten years ago at the salary shown in the table At the same time Sharla started at Company C at the salary shown in the table Who earned more during the last year How much more
20 Georgersquos page contains twice as many typed words as Billrsquos page and Billrsquos page contains 50 fewer words than Charliersquos page If each person can type 60 words per minute after one minute the difference between twice the number of words on Billrsquos page and the number of words on Charliersquos page is 210 How many words did Billrsquos page contain initially Use a table to organize the information
Initial number of words
Total number of words after one minute
Module 2 64 Lesson 2
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oug
hton
Mif
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Har
cour
t Pub
lishi
ng
Com
pan
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21 Geometry Sammie bought just enough fencing to border either a rectangular plot or a square plot as shown The perimeters of the plots are the same How many meters of fencing did she buy
HOT Focus on Higher Order Thinking
22 Justify Reasoning Suppose you want to solve the equation 2a + b = 2a where a and b are nonzero real numbers Describe the solution to this equation Justify your description
23 Multi-step A patio in the shape of a rectangle is fenced on all sides with 134 feet of fencing The patio is 5 feet less wide than it is long
a What information can be used to solve the problem How can you find the information
b Describe how to find the area of the patio What is the area of the patio
24 Explain the Error Kevin and Brittany write an equation to represent the following relationship and both students solve their equation Who found the correct equation and solution Why is the other person incorrect
5 times the difference of a number and 20 is the same as half the sum of 4 more than 4 times a number
Kevin Brittany
5 (x - 20) = 1 _ 2 (4x + 4) 5 (20 + x) = 1 _ 2 (4x + 4)
5x - 100 = 2x + 2 100 - 5x = 2x + 2
3x - 100 = 2 100 - 7x = 2
3x = 102 -7x = -98
x = 34 x = 14
(3x + 2) meters
(x + 2) meters
(x + 2) meters
(x - 1) meters
ℓ feet
(ℓ - 5) feet
Module 2 65 Lesson 2
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oug
hton Mifflin H
arcourt Publishin
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25 What If Alexa and Zack are solving the following problem
The number of miles on Car A is 50 miles more than the number of miles on Car B and the number of miles on Car B is 30 miles more than the number of miles on Car C All the cars travel 50 miles in 1 hour After 1 hour twice the number of miles on Car A is 70 miles less than 3 times the number of miles on Car C How many miles were there on Car B initially
Alexa assumes there are m miles on Car B Zack assumes there are m miles on Car C Will Zackrsquos answer be the same as Alexarsquos answer Explain
Lesson Performance Task
Stacy Oliver and Jivesh each plan to put a certain amount of money into their savings accounts that earn simple interest of 6 per year Stacy puts $550 more than Jivesh and Oliver puts in 2 times as much as Jivesh After a year the amount in Stacyrsquos account is 2 times the sum of $212 and the amount in Oliverrsquos account How much does each person initially put into his or her account Who had the most money in his or her account after a year Who had the least Explain
Zackrsquos Table Initial Miles
Miles after One Hour
Alexarsquos Table Initial Miles
Miles after One Hour
Amount in Account Initially Amount in Account after One Year
Module 2 66 Lesson 2
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oug
hton
Mif
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cour
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lishi
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pan
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Name Class Date
Resource Locker
Explore Rearranging Mathematical FormulasLiteral Equations are equations that contain two or more variables There are many literal equations in the form of math science and engineering formulas These formulas may seem like they can only be solved for the variable that is isolated on one side of the formula By using inverse operations and the properties of equality a formula can be rearranged so any variable in the formula can be isolated It is no different than how equations are solved by using inverse operations and the properties of equality
How can you solve the equation 42 = 6x
A42 _ = 6x _ What is the reason for dividing
Why divide by
= x By rearranging the equation x was isolated and the solution was found
The mathematical formula for the volume of a rectangular prism B = Vh or V = ℓwh is a literal equation V represents volume ℓ represents length w represents width and h represents height Using inverse operations the formula can be rearranged to solve for any one of the variables that might be unknown Like solving for x a formula can be rearranged to isolate a variable
B In the formula V = ℓwh the variable h needs to be isolated
The operation of is used in the formula The inverse
operation should be used
to isolate
C V _____ = ℓwh _____
V _ =
The formula rearranged in this way can easily produce the height of the rectangular prism when the volume length and width are known
Reflect
1 Using the formula for a rectangular prism rewrite the formula to solve for ℓ
ℓw
h
Module 2 67 Lesson 3
23 Solving for a VariableEssential Question How do you rewrite formulas and literal equations
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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Photo
grap
hyAurora Ph
otosCorb
is
Explain 1 Rearranging Scientific FormulasUse inverse operations to isolate the unknown variable in a scientific formula
The formula for density is D = m __ V Lead has a very high density of 11340 kg m 3 Plastic foam has a very low density of 75 kg m 3 The formula for density can be rearranged to solve for V volume or m mass
Example 1
A A sinker on a fishing line is made of lead and has a volume of 0000015 m 3 What is the mass of the sinker
The density formula can be rearranged to isolate m the mass The values for volume and density can then be substituted into the formula to find the mass
D = m _ V
DV = ( m _ V ) V DV = m
(11340 kg m 3 ) (0000015 m 3 ) = m
017 kg asymp m
B The design for a life preserver requires 03 kilogram of plastic foam to provide proper buoyancy What is the volume of the plastic foam required
Rearrange the density formula to isolate V
D = m _ V
(D) V = m _ V
DV =
DV _ = m _
V =
Now substitute the given values
V = _
V = m 3
Your Turn
2 For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Determine the altitude in feet when t is -275 ∘F and g is 60 ∘F
Module 2 68 Lesson 3
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cour
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Explain 2 Rearranging Literal EquationsUsing inverse operations to rearrange literal equations can be applied to any formula The interest formula I = prt is another example of a literal equation In the formula I represents interest p the principal or the initial amount to which interest will be applied r the rate at which interest will be paid and t is the time in years
Example 2
A Find the number of years used in the calculation of a $1000 loan at an interest rate of 5 with interest totaling $600
Solve the formula for t
I = prt
I _ pr = prt
_ pr
I _ pr = t
Substitute the given values Since the interest rate is 5 r = 005$600 __
$1000 middot 005 = t
12 = t
So the length of time for the loan is 12 years
B Determine the interest rate for a $2000 loan that will be paid off in 4 years with interest totaling $640 In order to find the interest rate solve the formula for r
I = prt
I _ = prt _
_ = r
Now substitute the values and simplify
__
( ) ( ) = r
008 = r
So the interest rate is per year
Your Turn
3 The formula y = mx + b is the slope-intercept form of the equation of a line Solve the equation for m
Module 2 69 Lesson 3
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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arcourt Publishin
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pany
bull Online Homeworkbull Hints and Helpbull Extra Practice
Solve for the indicated variable in each mathematical formula
1 C = 2πr for r 2 A = 1 __ 2 bh for b 3 y = mx + b for x
4 A = 1 __ 2 (a + b)h for h 5 V = πr2h for h 6 SA = 2πr2 + 2πrh for h
Solve for the indicated variable in each scientific formula
7 d = rt for t 8 PV = nRT for T
9 A = FV - OV _______ T for OV 10 C = Wtc _ 1000 for W
Evaluate Homework and Practice
Elaborate
4 Discussion What could be a reason for isolating a variable in a literal equation
5 Describe a situation in which a formula could be used more easily if it were rearranged Include the formula in your description
6 Essential Question Check-In How do you isolate a variable
Module 2 70 Lesson 3
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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oug
hton
Mif
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cour
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Com
pan
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mag
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copyO
cean
C
orb
is
Solve for the indicated variable in each literal equation
11 2p + 5r = q for p 12 -10 = xy + z for x 13 a __ b = c for b
14 h - 4 _ j = k for j 15 x __ 5 - g = a for x 16 5p + 9c = p for c
17 2 __ 5 (z + 1) = y for z 18 g (h + 2 __ 3 ) = 1 for h 19 a(n - 3) + 8 = bn for n
20 Which is a possible way to rewrite the equation y = 3x + 3b to solve for b
A b = y - 3x
_ 3 C b = y - 3
_____ 3x
B b = 3(y - 3x) D b = x(y - 3)
21 Sports To find a baseball pitcherrsquos earned run average (ERA) you can use the formula Ei = 9r in which E represents ERA i represents the number of innings pitched and r represents the number of earned runs allowed Solve the equation for E What is a pitcherrsquos ERA if he allows 5 earned runs in 18 innings pitched
22 Meteorology For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Solve the equation for a If the atmospheric temperature is -655 ∘F and the ground temperature is 57 ∘F what is the altitude
Module 2 71 Lesson 3
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
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arcourt Publishin
g Com
pany bull Im
age C
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Rand
y D
uch
aineA
lamy
HOT Focus on Higher Order Thinking
23 Explain the Error A student was asked to use the formula for the perimeter of a rectangle P = 2ℓ + 2w to solve for ℓ The student came up with an answer P - 2w = 2ℓ What error did the student make Explain Then solve for ℓ
24 Multi-Step The formula c = 5p + 215 relates c the total cost in dollars of hosting a birthday party at a skating rink to p the number of people attending If Alliersquos parents are willing to spend $300 for a party how many people can attend
25 Multi-Step The formula for the area of a triangle is A = 1 __ 2 bh in which b represents the length of thebase and h represents the height If a triangle has an area of 192 mm2 and the height is 12 mm what is the measure of the base
Lesson Performance TaskThe following table shows the average low temperatures in Fahrenheit for the city of Boston for several months during the year The formula F = 9 __ 5 C + 32 allows you to determine the temperature in Fahrenheit when given the temperature in Celsius
MonthTemperature in
FahrenheitTemperature in
Celsius
January 22deg
April 41deg
July 65deg
October 47deg
December 28deg
a Use the information given to determine the average low temperatures in Celsius
b Would it ever be possible for the temperature in Celsius to have a greater value than the temperature in Fahrenheit Explain why or why not
Module 2 72 Lesson 3
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
Name Class Date
Resource Locker
copy H
oug
hton
Mif
flin
Har
cour
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Com
pan
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mag
e cr
edit
s copy
Patr
ick
Lan
eSo
mos
Imag
esC
orb
is
Explore Creating Inequalities from Verbal DescriptionsAn inequality is a statement that compares two expressions that are not strictly equal by using one of the following inequality signs
Symbol Meaning
lt is less than
le is less than or equal to
gt is greater than
ge is greater than or equal to
ne is not equal to
You have probably seen a sign at an amusement park saying something like ldquoYou must be at least 48 inches tall to ride this riderdquo This statement could be written as h ge 48 in where h represents the height of a person allowed to ride
Nora is planning a birthday party for her little sister Colleen Norarsquos budget will allow her to spend no more than $50 for party supplies Eight children including Colleen will attend the party and Nora wants to determine how much she could spend on party favors for each child She will also purchase a cake for $10 Write an inequality that represents the situation and find possible solutions
A First let c represent the cost of a party favor for each child Write an expression for the total cost of the party as a function of c
c +
B Which inequality symbol should be used to represent the phrase ldquono more thanrdquo
C Write the inequality that represents Norarsquos budget goal
8c + 10 le
D Suppose Nora finds party favors that cost $4 each Use a value of 4 for c and check to see if this inequality is true
8 middot 4 + 10 le 50
le 50
Module 2 73 Lesson 4
24 Creating and Solving Inequalities
Essential Question How do you write and solve an inequality that represents a real-world situation
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany
Is the inequality true
Could Nora buy $6 party favors for all of her guests without going over budget
Reflect
1 Why does an inequality represent Norarsquos budget calculation better than an equation
2 The solution set of an inequality consists of all values that make the statement true Describe the whole dollar amounts that are in the solution set for this situation
Explain 1 Creating and Solving Inequalities Involving the Distributive Property
You may need to use the Distributive Property before you can solve an inequality
Distributive Property If a b and c are real numbers then a(b + c) = ab + ac
The inequality sign must be reversed when multiplying or dividing both sides of an inequality by a negative number
Example 1
A Trina is buying 12 shirts for the drama club She will choose a style for the blank shirts and then pay an additional charge of $275 for each shirt to have the club logo If Trina cannot spend more than $99 how much can she spend on each blank shirt Write and solve an inequality to find the possible cost of each blank shirt
Let s represent the cost of each blank shirt
Write an inequality to represent the situation 12(s + 275) le 99
Use the Distributive Property 12s + 33 le 99
Subtraction Property of Inequality 12s + 33 - 33 le 99 - 33
Simplify 12s le 66
Division Property of Inequality 12s ___ 12 le 66 __ 12
Simplify s le 55
Module 2 74 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
copy H
oug
hton
Mif
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Har
cour
t Pub
lishi
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Com
pan
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Check your answer
Since s le 55 check a smaller number 12(5 + 275) le 99
Trina can order blank shirts that cost $550 or less 93 le 99 true
B Sergio needs to buy gifts for 8 friends He wants to give the same gift to all his friends and he plans to have the gifts wrapped for an additional charge of $150 each If Sergio spends at least $70 he will receive free shipping on his order Write and solve an inequality to determine how much Sergio needs to spend on each gift in order to receive free shipping
Let g be the cost of one gift
Write an inequality to represent the situation ( g + ) ge 70
Use the Distributive Property g + ge 70
Subtraction Property of Inequality g + 12 - ge 70 -
Simplify 8g ge
Division Property of Inequality 8g _
ge 58 _
Simplify g ge
Check your answer
Since g ge 725 check a larger number 8(8 + 150) ge 70
Sergio must spend at least on each gift ge 70
Reflect
3 Discussion Why is the first step in solving the inequality to use the Distributive Property instead of working inside the parentheses
Your Turn
4 Zachary is planning to send a video game to each of his two brothers If he buys the same game for both brothers and pays $475 to ship each game how much can he spend on each game without spending more than $100 Write and solve an inequality for this situation
Solve each inequality
5 4 _ 3 (6x + 9) lt 4 6 -2 ( 1 _ 4 x + 2 ) ge 5
Module 2 75 Lesson 4
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Explain 2 Creating and Solving Inequalities with Variables on Both Sides
Some inequalities have variable terms on both sides of the inequality symbol You can solve these inequalities the same way you solved equations with variables on both sides Use the properties of inequality to collect all the variable terms on one side and all the constant terms on the other side
Example 2
A The Daily Info charges a fee of $650 plus $80 per week to run an ad The Peoplersquos Paper charges $145 per week For how many weeks must an ad run for the total cost at the Daily Info to be less expensive than the cost at the Peoplersquos Paper Let w be the number of weeks the ad runs in the paper
Write an inequality to represent the situation 650 + 80w lt 145w
Subtraction Property of Inequality 650 + 80w - 80w lt 145w - 80w
Simplify 650 lt 65w
Division Property of Inequality 650 _ 65 lt 65w _ 65
Simplify 10 lt w
The total cost at the Daily Info is less than the cost at the Peoplersquos Paper if the ad runs for more than 10 weeks
B The Home Cleaning Company charges $312 to power-wash the siding of a house plus $12 for each window Power Clean charges $36 per window and the price includes power-washing the siding How many windows must a house have to make the total cost from The Home Cleaning Company less expensive than Power Clean Let w be the number of windows
Write an inequality to represent the situation +12w lt 36w
Subtraction Property of Inequality 312 + 12w - lt 36w -
Simplify 312 lt
Division Property of Inequality 312 _ lt 24w _
Simplify lt w
A house must have more than 13 windows for The Home Cleaning Company to be less expensive than Power Clean
Reflect
7 How would the final inequality change if you divided by ndash24 in the next to last step
Your Turn
8 The school band will sell pizzas to raise money for new uniforms The supplier charges $100 plus $4 per pizza The band members sell the pizzas for $7 each Write and solve an inequality to find how many pizzas the band members will have to sell to make a profit
Module 2 76 Lesson 4
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Elaborate
9 Which inequality symbol would you use to represent the following words or phrases Can you come up with more examples
a at most b farther than c younger than d up to
10 Discussion How are the steps to solving an inequality similar to those for solving an equation How are they different
11 Essential Question Check-In How can you write an inequality that represents a real-world situation
Write an inequality that represents the description and then solve
1 Max has more than 5 carrots (number of carrots Max has = c)
2 Brigitte is shorter than 5 feet (Brigittersquos height = h)
3 Twice a number (x) is less than 10 4 Six more than five times a number (x) is at least twenty-one
5 Dave has $15 to spend on an $8 book and two birthday cards (c) for his friends How much can he spend on each card if he buys the same card for each friend
6 Toni can carry up to 18 lb in her backpack Her lunch weighs 1 lb her gym clothes weigh 2 lb and her books (b) weigh 3 lb each How many books can she carry in her backpack
Evaluate Homework and Practice
bull Online Homeworkbull Hints and Helpbull Extra Practice
Module 2 77 Lesson 4
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pany
Solve each inequality
7 3 (x - 2) gt -3 8 5 + 5 (x + 4) le 20 9 3 + 1 _ 2 (3 - x) lt -7
10 3 (x + 6) - 2 (x + 2) ge 10 11 5 (3 - x) -4 (2 - 3x) gt 2 12 1 _ 2 (4x - 2) - 2 _ 3 (6x + 9) le 4
13 x + 1 gt -5 (7 - 2x) 14 5 _ 3 (6x + 3) le 2x - 7
15 2x le - 2 __ 3 (4x + 4) 16 1 __ 2 (-2x - 10) gt 3 (4 - 6x)
17 -5 - 3x ge 2 (10 + 2x) + 3 18 -3 (9x + 20) ge 15x - 20
19 8 ( 1 _ 4 x - 3) + 24 lt 4 ( x + 5 ) 20 6x - 2 (x + 2) gt 2 - 3 (x + 3)
Module 2 78 Lesson 4
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21 Physics A crane cable can support a maximum load of 15000 kg If a bucket has a mass of 2000 kg and gravel has a mass of 1500 kg for every cubic meter how many cubic meters of gravel (g) can be safely lifted by the crane
22 Find the solution set of each inequality below and then determine which inequalities have the same solution set as 1 _ 3 ( -5x - 3 ) lt 14
a 1 _ 3 (5x + 3) gt -14 b 2 _ 5 (10x + 20) gt 44
c - 2 _ 5 (10x + 20) lt -44 d - 1 _ 3 (5x + 3) lt 14
e 2 _ 5 (10x - 20) gt -44 f 1 _ 3 (5x + 3) lt -14
HOT Focus on Higher Order Thinking
23 Explain the Error Sven is trying to find the maximum amount of time he can spend practicing the five scales of piano music he is supposed to be working on He has 60 minutes to practice piano and would like to spend at least 35 minutes playing songs instead of practicing scales So Sven sets up the following inequality where t is the number of minutes he spends on each scale and solves it
60 - 5t le 35-5t le -25
t ge 5
Sven has concluded that he should spend 5 minutes or more on each scale Is this correct If not what mistake did he make Then solve for the correct answer
Module 2 79 Lesson 4
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24 Critical Thinking Anika wants to determine the maximum number of tulip bulbs (t) she can purchase if each bulb costs $150 She will also need to purchase separate pots for each bulb at $125 each and a bag of potting soil for $1000 Set up an inequality to determine how many tulip bulbs Anika can purchase without spending more than $2000 and solve it Can Anika buy exactly enough bulbs and pots to spend the full $2000 Explain Can you think of a better inequality to describe the answer
25 Geometry The area of the triangle shown is no more than 10 square inches
a Write an inequality that can be used to find x
b Solve the inequality from part a c What is the maximum height of the triangle
Lesson Performance TaskWhen planning an airplane route the trip planner must be careful to consider the range the aircraft can travel and the availability of airports to stop and refuel
A large commercial jet airplane burns approximately 5 gallons of fuel per mile flown plus about 8500 gallons of fuel per trip to reach cruising altitude With a useable fuel capacity of 50000 gallons (there is additional fuel reserved for emergencies) describe the acceptable distance for which an airline could establish a non-stop flight
For flights originating from Chicago determine which cities could be safely reached by a non-stop flight
City Distance from Chicago (miles)
Bangalore India 8530
Jakarta Indonesia 9810
Johannesburg South Africa 8680
Moscow Russia 4970
Paris France 4130
Perth Australia 10970
Tokyo Japan 6300
copy H
oug
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age cred
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eva O
lesiaShutterstock
(2x - 3) in
4 in
Module 2 80 Lesson 4
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Name Class Date
Resource Locker
Explore Truth Tables and Compound StatementsA compound statement is formed by combining two or more simple statements A compound statement can be true or false A compound statement involving AND is true when both simple statements are true A compound statement involving OR is true when either one simple statement or both are true
A Complete the truth table
P QP
True or FalseQ
True or FalseP AND Q
True or False
A dog is a mammal Red is a color
A dog is a mammal Red is not a color
A dog is a fish Red is a color
A dog is a fish Red is not a color
B P AND Q is true when
C Complete the truth table
P QP
True or FalseQ
True or FalseP OR Q
True or False
1 is an odd number 2 is an even number
1 is an odd number 2 is an odd number
1 is an even number 2 is an even number
1 is an even number 2 is an odd number
D P OR Q is true when
Reflect
1 Give two simple statements P and Q for which P AND Q is false and P OR Q is true
Module 2 81 Lesson 5
25 Creating and Solving Compound Inequalities
Essential Question How can you solve a compound inequality and graph the solution set
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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Explain 1 Solving Compound Inequalities Involving ANDCombining two or more simple inequalities forms a compound inequality The graph of a compound inequality involving AND is the intersection or the overlapping region of the simple inequality graphs
Compound Inequalities AND
Words Algebra Graph
All real numbers greater than 2AND less than 6
x gt 2 AND x lt 62 lt x lt 6
All real numbers greater than or equal to 2 AND less than or equal to 6
x ge 2 AND x le 62 le x le 6
Example 1 Solve each compound inequality and graph the solutions
A 4 le x + 2 le 8
4 le x + 2 AND x + 2 le 8 Write the compound inequality using AND
4 - 2 le x + 2 - 2 x + 2 - 2 le 8 - 2 Subtract 2 from both sides of each simple inequality
2 le x x le 6 Simplify
Graph 2 le x
Graph x le 6
Graph the intersection by finding where the two graphs overlap
B -5 le 2x + 3 lt 9
-5 - le 2x + 3 - lt 9 - Subtract from each part of the inequality
le 2x lt Simplify
-8 _ le 2x _ lt 6 _ Divide each part of the inequality by
le x lt Simplify
Graph -4 le x
Graph x lt 3
Graph the intersection by finding where the two graphs overlap -1 0 1 2 3 4 5-5-4 -3 -2
0 2 4 6 8 10 12-8-6-4 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 82 Lesson 5
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Reflect
2 Discussion Explain why 2 le x le 6 can be considered the short method for writing the AND compound inequality x ge 2 AND x le 6
YourTurn
Solve each compound inequality and graph the solutions
3 -2 lt x - 3 lt 5
4 -10 lt 3x + 2 le 8
Explain 2 Solving Compound Inequalities Involving ORThe graph of a compound inequality involving OR is the union or the combined region of the simple inequality graphs
Compound Inequalities OR
Words Algebra Graph
All real numbers less than 2OR greater than 6
x lt 2 OR x gt 6
All real numbers less than or equal to 2OR greater than or equal to 6
x le 2 OR x ge 6
-1 0 1 2 3 4 5-5-4 -3 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 83 Lesson 5
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oug
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Example 2 Solve each compound inequality and graph the solutions
A -4 + x gt 1 OR -4 + x lt -3
-4 + x gt 1 OR -4 + x lt -3 Write the compound inequality using OR
-4 + 4 + x gt 1 + 4 -4 + 4 + x lt -3 + 4 Add 4 to both sides of each simple inequality
x gt 5 x lt 1 Simplify
Graph x gt 5
Graph x lt 1
Graph the union by combining the graphs
B 2x le 6 OR 3x gt 12
2x le 6 OR 3x gt 12 Write the compound inequality using OR
2x _ le 6 _ OR 3x _ gt 12 _ Divide the first simple inequality by
x le OR x gt
Graph x le 3
Graph x gt 4
Graph the union by combining the graphs
Reflect
5 Critical Thinking What kind of compound inequality has no solution
Divide the second simple inequality by
Simplify
0 1 2 3 4 5 6-4 -3 -2 -1
-0 1 2 3 4 5 6-4 -3 -2 -1
Module 2 84 Lesson 5
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oug
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Your Turn
Solve each compound inequality and graph the solutions
6 x - 5 ge -2 OR x -5 le -6
7 4x -1 lt 15 OR 8x ge 48
Explain 3 Creating Compound Inequalities From GraphsGiven a number line graph with a solution set graphed you can create a compound inequality to fit the graph
Example 3 Write the compound inequality shown by each graph
A
The shaded portion of the graph is not between two values so the compound inequality involves OR
On the left the graph shows an arrow pointing left from -1 and a solid circle so use le
The inequality is x le -1
On the right the graph shows an arrow pointing right from 7 and a solid circle so use ge
The inequality is x ge 7
The compound inequality is x le -1 OR x ge 7
B
The graph is shaded between the values and so the compound inequality involves AND
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The compound inequality is
-1 0 1 2 3 4 5-5-4 -3 -2
4 5 6 7 8 9 100 1 2 3
2 3 4 5 6 7 8-2 -1 0 1
10 2 3 4 5 6 7 8 9-1
Module 2 85 Lesson 5
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oug
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pany
Reflect
8 What is a short method to write the compound inequality x ge 0 AND x lt 6
Your Turn
Write the compound inequality shown by each graph
9
10
Explain 4 Expressing Acceptable Levels with Compound Inequalities
You can express quality-controls levels in real-world problems using compound inequalities
Example 4 Write a compound inequality to represent the indicated quality-control level and graph the solutions
A The recommended pH level for swimming pool water is between 72 and 76 inclusive
Let p be the pH level of swimming pool water
72 is less than or equal to pH level is less than or equal to 76
72 le p le 76
The compound inequality is 72 le p le 76
Graph the solutions
0-10 -8-9 -7-6 -5-4 -3 -2 -1
71 72 73 74 75 76 77 78 79 8070
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 86 Lesson 5
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oug
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pan
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B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
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oug
hton Mifflin H
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pany
bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
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oug
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Com
pan
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Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
arcourt Publishin
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pany bull Im
age C
redits copy
Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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Mif
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cour
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Com
pan
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mag
e C
red
its
copy
bik
erid
erlo
nd
onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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Your Turn
Write and solve an equation to solve the problem
5 A rectangular garden is fenced on all sides with 256 feet of fencing The garden is 8 feet longer than it is wide Find the length and width of the garden
Explain 2 Creating and Solving Equations with Variables on Both Sides
In some equations variables appear on both sides You can use the properties of equality to collect the variable terms so that they all appear on one side of the equation
Example 2 Write and solve an equation to solve each problem
A Janine has job offers at two companies One company offers a starting salary of $28000 with a raise of $3000 each year The other company offers a starting salary of $36000 with a raise of $2000 each year In how many years would Janinersquos salary be the same with both companies What will the salary be
Write a verbal description of the basic situation
Let n represent the number of years it takes for the salaries to be equal
Base Salary A plus $3000 per year raise = Base Salary B + $2000 per year raise
28000 + 3000n = 36000 + 2000n
28000 + 3000n - 2000n = 36000 + 2000n - 2000n Subtraction Property of Equality
28000 + 1000n = 36000 Combine like terms
28000 + 1000n - 28000 = 36000 - 28000 Subtraction Property of Equality
1000n = 8000 1000n _ 1000 = 8000 _ 1000 Division Property of Equality
n = 8
28000 + 3000 (8) = 36000 + 2000 (8)
52000 = 52000
In 8 years the salaries offered by both companies will be $52000
(w + 8) feet
w feet
Module 2 58 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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pan
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B One moving company charges $800 plus $16 per hour Another moving company charges $720 plus $21 per hour At what number of hours will the charge by both companies be the same What is the charge
Write a verbal description of the basic situation Let t represent the number of hours that the move takes
Moving Charge A plus $16 per hour = Moving Charge B plus $21 per hour
800 + t = 720 + t
800 + t - t = 720 + t - t Subtraction Property of Equality
800 = 720 + t
800 - 720 = 720 + t - 720 Subtraction Property of Equality
= t
_ = t _
Division Property of Equality
t =
The charges are the same for a job that takes hours
Substitute the value 16 in the original equation
800 + 16t = 720 + 21t
800 + 16 ( ) = 720 + 21 ( ) 800 + = 720 +
=
After hours the moving charge for both companies will be
Reflect
6 Suppose you collected the variable terms on the other side of the equal sign to solve the equation Would that affect the solution
Module 2 59 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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pany
Your Turn
Write and solve an equation to solve each problem7 Claire bought just enough fencing to enclose either a
rectangular garden or a triangular garden as shown The two gardens have the same perimeter How many feet of fencing did she buy
8 A veterinarian is changing the diets of two animals Simba and Cuddles Simba currently consumes 1200 Calories per day That number will increase by 100 Calories each day Cuddles currently consumes 3230 Calories a day That number will decrease by 190 Calories each day The patterns will continue until both animals are consuming the same number of Calories each day In how many days will that be How many Calories will each animal be consuming each day then
Explain 3 Constructing Equations from an Organized TableYou can use a table to organize information and see relationships
Example 3 Construct and solve an equation to solve the problem
Kim works 4 hours more each day than Jill does and Jack works 2 hours less each day than Jill does Over 2 days the number of hours Kim works is equal to the difference of 4 times the number of hours Jack works and the number of hours Jill works How many hours does each person work each day
Analyze Information
Identify the important information
bull Kim works hours more per day than Jill does
bull Jack works hours less per day than Jill does
Formulate a Plan
Make a table using the information given Let x be the number of hours Jill works in one day
Hours Worked Per Day Hours Worked Over 2 Days
Kim
Jill
Jack
Over 2 days the number of hours Kim works is equal to the difference of 4 times the number of hours Jack works and the number of hours Jill works
(3x - 3)(x - 3)
(2x - 1) (2x - 1)
2x
Module 2 60 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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Solve
2 (x + 4) = 4 2 (x - 2) - 2x
2 (x + 4) = (x - 2) - 2x Simplify
2x + = 8x - - 2x Distributive Property
2x + 8 = x - 16
2x + 8 + = 6x - 16 + Addition Property of Equality
2x + = 6x
2x + 24 - x = 6x - x Subtraction Property of Equality
24 = x
24 _ = x _ Division Property of Equality
= x
Jill works hours per day Kim works hours per day and Jack works
hours per day
Justify and Evaluate
Substitute x = 6 into the original equation
2 (6 + 4) = 4 2 (6 - 2) - 2x
2 ( ) = 8 ( ) - 2 ( ) =
Your Turn
Write and solve an equation to solve the problem
9 Lisa is 10 centimeters taller than her friend Ian Ian is 14 centimeters taller than Jim Every month their heights increase by 2 centimeters In 7 months the sum of Ianrsquos and Jimrsquos heights will be 170 centimeters more than Lisarsquos height How tall is Ian now
Height now Height after 7 months
Module 2 61 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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oug
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pany
Elaborate
10 How can you use properties to solve equations with variables on both sides
11 How is a table helpful when constructing equations
12 When solving a real-world problem to find a personrsquos age would a negative solution make sense Explain
13 Essential Question Check-In How do you write an equation to represent a real-world situation
bull Online Homeworkbull Hints and Helpbull Extra Practice
Write an equation for each description
1 The sum of 14 and a number is equal to 17 2 A number increased by 10 is 114
3 The difference between a number and 12 is 20 4 Ten times the sum of half a number and 6 is 8
5 Two-thirds a number plus 4 is 7 6 Tanmayi wants to raise $175 for a school fundraiser She has raised $120 so far How much more does she need to reach her goal
7 Hector is visiting a cousin who lives 350 miles away He has driven 90 miles How many more miles does he need to drive to reach his cousinrsquos home
8 The length of a rectangle is twice its width The perimeter of the rectangle is 126 feet
Evaluate Homework and Practice
Module 2 62 Lesson 2
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Pete
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imS
hutt
erst
ock
Write and solve an equation for each situation
9 In one baseball season Peter hit twice the difference of the number of home runs Alice hit and 6 Altogether they hit 18 home runs How many home runs did each player hit that season
10 The perimeter of a parallelogram is 72 meters The width of the parallelogram is 4 meters less than its length Find the length and the width of the parallelogram
11 One month Ruby worked 6 hours more than Isaac and Svetlana worked 4 times as many hours as Ruby Together they worked 126 hours Find the number of hours each person worked
12 In one day Annie traveled 5 times the sum of the number of hours Brian traveled and 2 Together they traveled 20 hours Find the number of hours each person traveled
13 Xian and his cousin Kai both collect stamps Xian has 56 stamps and Kai has 80 stamps The boys recently joined different stamp-collecting clubs Xianrsquos club will send him 12 new stamps per month Kairsquos club will send him 8 new stamps per month After how many months will Xian and Kai have the same number of stamps How many stamps will each have
14 Kenya plans to make a down payment plus monthly payments in order to buy a motorcycle At one dealer she would pay $2500 down and $150 each month At another dealer she would pay $3000 down and $125 each month After how many months would the total amount paid be the same for both dealers What would that amount be
ℓ meters
(ℓ - 4) meters
Module 2 63 Lesson 2
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15 Community Gym charges a $50 membership fee and a $55 monthly fee Workout Gym charges a $200 membership fee and a $45 monthly fee After how many months will the total amount of money paid to both gyms be the same What will the amount be
16 Tina is saving to buy a notebook computer She has two options The first option is to put $200 away initially and save $10 every month The second option is to put $100 away initially and save $30 every month After how many months would Tina save the same amount using either option How much would she save with either option
Use the table to answer each question
Starting Salary Yearly Salary Increase
Company A $24000 $3000
Company B $30000 $2400
Company C $36000 $2000
17 After how many years are the salaries offered by Company A and Company B the same
18 After how many years are the salaries offered by Company B and Company C the same
19 Paul started work at Company B ten years ago at the salary shown in the table At the same time Sharla started at Company C at the salary shown in the table Who earned more during the last year How much more
20 Georgersquos page contains twice as many typed words as Billrsquos page and Billrsquos page contains 50 fewer words than Charliersquos page If each person can type 60 words per minute after one minute the difference between twice the number of words on Billrsquos page and the number of words on Charliersquos page is 210 How many words did Billrsquos page contain initially Use a table to organize the information
Initial number of words
Total number of words after one minute
Module 2 64 Lesson 2
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pan
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21 Geometry Sammie bought just enough fencing to border either a rectangular plot or a square plot as shown The perimeters of the plots are the same How many meters of fencing did she buy
HOT Focus on Higher Order Thinking
22 Justify Reasoning Suppose you want to solve the equation 2a + b = 2a where a and b are nonzero real numbers Describe the solution to this equation Justify your description
23 Multi-step A patio in the shape of a rectangle is fenced on all sides with 134 feet of fencing The patio is 5 feet less wide than it is long
a What information can be used to solve the problem How can you find the information
b Describe how to find the area of the patio What is the area of the patio
24 Explain the Error Kevin and Brittany write an equation to represent the following relationship and both students solve their equation Who found the correct equation and solution Why is the other person incorrect
5 times the difference of a number and 20 is the same as half the sum of 4 more than 4 times a number
Kevin Brittany
5 (x - 20) = 1 _ 2 (4x + 4) 5 (20 + x) = 1 _ 2 (4x + 4)
5x - 100 = 2x + 2 100 - 5x = 2x + 2
3x - 100 = 2 100 - 7x = 2
3x = 102 -7x = -98
x = 34 x = 14
(3x + 2) meters
(x + 2) meters
(x + 2) meters
(x - 1) meters
ℓ feet
(ℓ - 5) feet
Module 2 65 Lesson 2
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25 What If Alexa and Zack are solving the following problem
The number of miles on Car A is 50 miles more than the number of miles on Car B and the number of miles on Car B is 30 miles more than the number of miles on Car C All the cars travel 50 miles in 1 hour After 1 hour twice the number of miles on Car A is 70 miles less than 3 times the number of miles on Car C How many miles were there on Car B initially
Alexa assumes there are m miles on Car B Zack assumes there are m miles on Car C Will Zackrsquos answer be the same as Alexarsquos answer Explain
Lesson Performance Task
Stacy Oliver and Jivesh each plan to put a certain amount of money into their savings accounts that earn simple interest of 6 per year Stacy puts $550 more than Jivesh and Oliver puts in 2 times as much as Jivesh After a year the amount in Stacyrsquos account is 2 times the sum of $212 and the amount in Oliverrsquos account How much does each person initially put into his or her account Who had the most money in his or her account after a year Who had the least Explain
Zackrsquos Table Initial Miles
Miles after One Hour
Alexarsquos Table Initial Miles
Miles after One Hour
Amount in Account Initially Amount in Account after One Year
Module 2 66 Lesson 2
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Name Class Date
Resource Locker
Explore Rearranging Mathematical FormulasLiteral Equations are equations that contain two or more variables There are many literal equations in the form of math science and engineering formulas These formulas may seem like they can only be solved for the variable that is isolated on one side of the formula By using inverse operations and the properties of equality a formula can be rearranged so any variable in the formula can be isolated It is no different than how equations are solved by using inverse operations and the properties of equality
How can you solve the equation 42 = 6x
A42 _ = 6x _ What is the reason for dividing
Why divide by
= x By rearranging the equation x was isolated and the solution was found
The mathematical formula for the volume of a rectangular prism B = Vh or V = ℓwh is a literal equation V represents volume ℓ represents length w represents width and h represents height Using inverse operations the formula can be rearranged to solve for any one of the variables that might be unknown Like solving for x a formula can be rearranged to isolate a variable
B In the formula V = ℓwh the variable h needs to be isolated
The operation of is used in the formula The inverse
operation should be used
to isolate
C V _____ = ℓwh _____
V _ =
The formula rearranged in this way can easily produce the height of the rectangular prism when the volume length and width are known
Reflect
1 Using the formula for a rectangular prism rewrite the formula to solve for ℓ
ℓw
h
Module 2 67 Lesson 3
23 Solving for a VariableEssential Question How do you rewrite formulas and literal equations
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hyAurora Ph
otosCorb
is
Explain 1 Rearranging Scientific FormulasUse inverse operations to isolate the unknown variable in a scientific formula
The formula for density is D = m __ V Lead has a very high density of 11340 kg m 3 Plastic foam has a very low density of 75 kg m 3 The formula for density can be rearranged to solve for V volume or m mass
Example 1
A A sinker on a fishing line is made of lead and has a volume of 0000015 m 3 What is the mass of the sinker
The density formula can be rearranged to isolate m the mass The values for volume and density can then be substituted into the formula to find the mass
D = m _ V
DV = ( m _ V ) V DV = m
(11340 kg m 3 ) (0000015 m 3 ) = m
017 kg asymp m
B The design for a life preserver requires 03 kilogram of plastic foam to provide proper buoyancy What is the volume of the plastic foam required
Rearrange the density formula to isolate V
D = m _ V
(D) V = m _ V
DV =
DV _ = m _
V =
Now substitute the given values
V = _
V = m 3
Your Turn
2 For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Determine the altitude in feet when t is -275 ∘F and g is 60 ∘F
Module 2 68 Lesson 3
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Explain 2 Rearranging Literal EquationsUsing inverse operations to rearrange literal equations can be applied to any formula The interest formula I = prt is another example of a literal equation In the formula I represents interest p the principal or the initial amount to which interest will be applied r the rate at which interest will be paid and t is the time in years
Example 2
A Find the number of years used in the calculation of a $1000 loan at an interest rate of 5 with interest totaling $600
Solve the formula for t
I = prt
I _ pr = prt
_ pr
I _ pr = t
Substitute the given values Since the interest rate is 5 r = 005$600 __
$1000 middot 005 = t
12 = t
So the length of time for the loan is 12 years
B Determine the interest rate for a $2000 loan that will be paid off in 4 years with interest totaling $640 In order to find the interest rate solve the formula for r
I = prt
I _ = prt _
_ = r
Now substitute the values and simplify
__
( ) ( ) = r
008 = r
So the interest rate is per year
Your Turn
3 The formula y = mx + b is the slope-intercept form of the equation of a line Solve the equation for m
Module 2 69 Lesson 3
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oug
hton Mifflin H
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pany
bull Online Homeworkbull Hints and Helpbull Extra Practice
Solve for the indicated variable in each mathematical formula
1 C = 2πr for r 2 A = 1 __ 2 bh for b 3 y = mx + b for x
4 A = 1 __ 2 (a + b)h for h 5 V = πr2h for h 6 SA = 2πr2 + 2πrh for h
Solve for the indicated variable in each scientific formula
7 d = rt for t 8 PV = nRT for T
9 A = FV - OV _______ T for OV 10 C = Wtc _ 1000 for W
Evaluate Homework and Practice
Elaborate
4 Discussion What could be a reason for isolating a variable in a literal equation
5 Describe a situation in which a formula could be used more easily if it were rearranged Include the formula in your description
6 Essential Question Check-In How do you isolate a variable
Module 2 70 Lesson 3
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pan
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mag
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cean
C
orb
is
Solve for the indicated variable in each literal equation
11 2p + 5r = q for p 12 -10 = xy + z for x 13 a __ b = c for b
14 h - 4 _ j = k for j 15 x __ 5 - g = a for x 16 5p + 9c = p for c
17 2 __ 5 (z + 1) = y for z 18 g (h + 2 __ 3 ) = 1 for h 19 a(n - 3) + 8 = bn for n
20 Which is a possible way to rewrite the equation y = 3x + 3b to solve for b
A b = y - 3x
_ 3 C b = y - 3
_____ 3x
B b = 3(y - 3x) D b = x(y - 3)
21 Sports To find a baseball pitcherrsquos earned run average (ERA) you can use the formula Ei = 9r in which E represents ERA i represents the number of innings pitched and r represents the number of earned runs allowed Solve the equation for E What is a pitcherrsquos ERA if he allows 5 earned runs in 18 innings pitched
22 Meteorology For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Solve the equation for a If the atmospheric temperature is -655 ∘F and the ground temperature is 57 ∘F what is the altitude
Module 2 71 Lesson 3
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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g Com
pany bull Im
age C
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Rand
y D
uch
aineA
lamy
HOT Focus on Higher Order Thinking
23 Explain the Error A student was asked to use the formula for the perimeter of a rectangle P = 2ℓ + 2w to solve for ℓ The student came up with an answer P - 2w = 2ℓ What error did the student make Explain Then solve for ℓ
24 Multi-Step The formula c = 5p + 215 relates c the total cost in dollars of hosting a birthday party at a skating rink to p the number of people attending If Alliersquos parents are willing to spend $300 for a party how many people can attend
25 Multi-Step The formula for the area of a triangle is A = 1 __ 2 bh in which b represents the length of thebase and h represents the height If a triangle has an area of 192 mm2 and the height is 12 mm what is the measure of the base
Lesson Performance TaskThe following table shows the average low temperatures in Fahrenheit for the city of Boston for several months during the year The formula F = 9 __ 5 C + 32 allows you to determine the temperature in Fahrenheit when given the temperature in Celsius
MonthTemperature in
FahrenheitTemperature in
Celsius
January 22deg
April 41deg
July 65deg
October 47deg
December 28deg
a Use the information given to determine the average low temperatures in Celsius
b Would it ever be possible for the temperature in Celsius to have a greater value than the temperature in Fahrenheit Explain why or why not
Module 2 72 Lesson 3
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
Name Class Date
Resource Locker
copy H
oug
hton
Mif
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Har
cour
t Pub
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Com
pan
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mag
e cr
edit
s copy
Patr
ick
Lan
eSo
mos
Imag
esC
orb
is
Explore Creating Inequalities from Verbal DescriptionsAn inequality is a statement that compares two expressions that are not strictly equal by using one of the following inequality signs
Symbol Meaning
lt is less than
le is less than or equal to
gt is greater than
ge is greater than or equal to
ne is not equal to
You have probably seen a sign at an amusement park saying something like ldquoYou must be at least 48 inches tall to ride this riderdquo This statement could be written as h ge 48 in where h represents the height of a person allowed to ride
Nora is planning a birthday party for her little sister Colleen Norarsquos budget will allow her to spend no more than $50 for party supplies Eight children including Colleen will attend the party and Nora wants to determine how much she could spend on party favors for each child She will also purchase a cake for $10 Write an inequality that represents the situation and find possible solutions
A First let c represent the cost of a party favor for each child Write an expression for the total cost of the party as a function of c
c +
B Which inequality symbol should be used to represent the phrase ldquono more thanrdquo
C Write the inequality that represents Norarsquos budget goal
8c + 10 le
D Suppose Nora finds party favors that cost $4 each Use a value of 4 for c and check to see if this inequality is true
8 middot 4 + 10 le 50
le 50
Module 2 73 Lesson 4
24 Creating and Solving Inequalities
Essential Question How do you write and solve an inequality that represents a real-world situation
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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pany
Is the inequality true
Could Nora buy $6 party favors for all of her guests without going over budget
Reflect
1 Why does an inequality represent Norarsquos budget calculation better than an equation
2 The solution set of an inequality consists of all values that make the statement true Describe the whole dollar amounts that are in the solution set for this situation
Explain 1 Creating and Solving Inequalities Involving the Distributive Property
You may need to use the Distributive Property before you can solve an inequality
Distributive Property If a b and c are real numbers then a(b + c) = ab + ac
The inequality sign must be reversed when multiplying or dividing both sides of an inequality by a negative number
Example 1
A Trina is buying 12 shirts for the drama club She will choose a style for the blank shirts and then pay an additional charge of $275 for each shirt to have the club logo If Trina cannot spend more than $99 how much can she spend on each blank shirt Write and solve an inequality to find the possible cost of each blank shirt
Let s represent the cost of each blank shirt
Write an inequality to represent the situation 12(s + 275) le 99
Use the Distributive Property 12s + 33 le 99
Subtraction Property of Inequality 12s + 33 - 33 le 99 - 33
Simplify 12s le 66
Division Property of Inequality 12s ___ 12 le 66 __ 12
Simplify s le 55
Module 2 74 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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oug
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Mif
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Har
cour
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lishi
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Com
pan
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Check your answer
Since s le 55 check a smaller number 12(5 + 275) le 99
Trina can order blank shirts that cost $550 or less 93 le 99 true
B Sergio needs to buy gifts for 8 friends He wants to give the same gift to all his friends and he plans to have the gifts wrapped for an additional charge of $150 each If Sergio spends at least $70 he will receive free shipping on his order Write and solve an inequality to determine how much Sergio needs to spend on each gift in order to receive free shipping
Let g be the cost of one gift
Write an inequality to represent the situation ( g + ) ge 70
Use the Distributive Property g + ge 70
Subtraction Property of Inequality g + 12 - ge 70 -
Simplify 8g ge
Division Property of Inequality 8g _
ge 58 _
Simplify g ge
Check your answer
Since g ge 725 check a larger number 8(8 + 150) ge 70
Sergio must spend at least on each gift ge 70
Reflect
3 Discussion Why is the first step in solving the inequality to use the Distributive Property instead of working inside the parentheses
Your Turn
4 Zachary is planning to send a video game to each of his two brothers If he buys the same game for both brothers and pays $475 to ship each game how much can he spend on each game without spending more than $100 Write and solve an inequality for this situation
Solve each inequality
5 4 _ 3 (6x + 9) lt 4 6 -2 ( 1 _ 4 x + 2 ) ge 5
Module 2 75 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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Explain 2 Creating and Solving Inequalities with Variables on Both Sides
Some inequalities have variable terms on both sides of the inequality symbol You can solve these inequalities the same way you solved equations with variables on both sides Use the properties of inequality to collect all the variable terms on one side and all the constant terms on the other side
Example 2
A The Daily Info charges a fee of $650 plus $80 per week to run an ad The Peoplersquos Paper charges $145 per week For how many weeks must an ad run for the total cost at the Daily Info to be less expensive than the cost at the Peoplersquos Paper Let w be the number of weeks the ad runs in the paper
Write an inequality to represent the situation 650 + 80w lt 145w
Subtraction Property of Inequality 650 + 80w - 80w lt 145w - 80w
Simplify 650 lt 65w
Division Property of Inequality 650 _ 65 lt 65w _ 65
Simplify 10 lt w
The total cost at the Daily Info is less than the cost at the Peoplersquos Paper if the ad runs for more than 10 weeks
B The Home Cleaning Company charges $312 to power-wash the siding of a house plus $12 for each window Power Clean charges $36 per window and the price includes power-washing the siding How many windows must a house have to make the total cost from The Home Cleaning Company less expensive than Power Clean Let w be the number of windows
Write an inequality to represent the situation +12w lt 36w
Subtraction Property of Inequality 312 + 12w - lt 36w -
Simplify 312 lt
Division Property of Inequality 312 _ lt 24w _
Simplify lt w
A house must have more than 13 windows for The Home Cleaning Company to be less expensive than Power Clean
Reflect
7 How would the final inequality change if you divided by ndash24 in the next to last step
Your Turn
8 The school band will sell pizzas to raise money for new uniforms The supplier charges $100 plus $4 per pizza The band members sell the pizzas for $7 each Write and solve an inequality to find how many pizzas the band members will have to sell to make a profit
Module 2 76 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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oug
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Mif
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cour
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Elaborate
9 Which inequality symbol would you use to represent the following words or phrases Can you come up with more examples
a at most b farther than c younger than d up to
10 Discussion How are the steps to solving an inequality similar to those for solving an equation How are they different
11 Essential Question Check-In How can you write an inequality that represents a real-world situation
Write an inequality that represents the description and then solve
1 Max has more than 5 carrots (number of carrots Max has = c)
2 Brigitte is shorter than 5 feet (Brigittersquos height = h)
3 Twice a number (x) is less than 10 4 Six more than five times a number (x) is at least twenty-one
5 Dave has $15 to spend on an $8 book and two birthday cards (c) for his friends How much can he spend on each card if he buys the same card for each friend
6 Toni can carry up to 18 lb in her backpack Her lunch weighs 1 lb her gym clothes weigh 2 lb and her books (b) weigh 3 lb each How many books can she carry in her backpack
Evaluate Homework and Practice
bull Online Homeworkbull Hints and Helpbull Extra Practice
Module 2 77 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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oug
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pany
Solve each inequality
7 3 (x - 2) gt -3 8 5 + 5 (x + 4) le 20 9 3 + 1 _ 2 (3 - x) lt -7
10 3 (x + 6) - 2 (x + 2) ge 10 11 5 (3 - x) -4 (2 - 3x) gt 2 12 1 _ 2 (4x - 2) - 2 _ 3 (6x + 9) le 4
13 x + 1 gt -5 (7 - 2x) 14 5 _ 3 (6x + 3) le 2x - 7
15 2x le - 2 __ 3 (4x + 4) 16 1 __ 2 (-2x - 10) gt 3 (4 - 6x)
17 -5 - 3x ge 2 (10 + 2x) + 3 18 -3 (9x + 20) ge 15x - 20
19 8 ( 1 _ 4 x - 3) + 24 lt 4 ( x + 5 ) 20 6x - 2 (x + 2) gt 2 - 3 (x + 3)
Module 2 78 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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pan
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21 Physics A crane cable can support a maximum load of 15000 kg If a bucket has a mass of 2000 kg and gravel has a mass of 1500 kg for every cubic meter how many cubic meters of gravel (g) can be safely lifted by the crane
22 Find the solution set of each inequality below and then determine which inequalities have the same solution set as 1 _ 3 ( -5x - 3 ) lt 14
a 1 _ 3 (5x + 3) gt -14 b 2 _ 5 (10x + 20) gt 44
c - 2 _ 5 (10x + 20) lt -44 d - 1 _ 3 (5x + 3) lt 14
e 2 _ 5 (10x - 20) gt -44 f 1 _ 3 (5x + 3) lt -14
HOT Focus on Higher Order Thinking
23 Explain the Error Sven is trying to find the maximum amount of time he can spend practicing the five scales of piano music he is supposed to be working on He has 60 minutes to practice piano and would like to spend at least 35 minutes playing songs instead of practicing scales So Sven sets up the following inequality where t is the number of minutes he spends on each scale and solves it
60 - 5t le 35-5t le -25
t ge 5
Sven has concluded that he should spend 5 minutes or more on each scale Is this correct If not what mistake did he make Then solve for the correct answer
Module 2 79 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
24 Critical Thinking Anika wants to determine the maximum number of tulip bulbs (t) she can purchase if each bulb costs $150 She will also need to purchase separate pots for each bulb at $125 each and a bag of potting soil for $1000 Set up an inequality to determine how many tulip bulbs Anika can purchase without spending more than $2000 and solve it Can Anika buy exactly enough bulbs and pots to spend the full $2000 Explain Can you think of a better inequality to describe the answer
25 Geometry The area of the triangle shown is no more than 10 square inches
a Write an inequality that can be used to find x
b Solve the inequality from part a c What is the maximum height of the triangle
Lesson Performance TaskWhen planning an airplane route the trip planner must be careful to consider the range the aircraft can travel and the availability of airports to stop and refuel
A large commercial jet airplane burns approximately 5 gallons of fuel per mile flown plus about 8500 gallons of fuel per trip to reach cruising altitude With a useable fuel capacity of 50000 gallons (there is additional fuel reserved for emergencies) describe the acceptable distance for which an airline could establish a non-stop flight
For flights originating from Chicago determine which cities could be safely reached by a non-stop flight
City Distance from Chicago (miles)
Bangalore India 8530
Jakarta Indonesia 9810
Johannesburg South Africa 8680
Moscow Russia 4970
Paris France 4130
Perth Australia 10970
Tokyo Japan 6300
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its copySarych
eva O
lesiaShutterstock
(2x - 3) in
4 in
Module 2 80 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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Mif
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Har
cour
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Com
pan
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Name Class Date
Resource Locker
Explore Truth Tables and Compound StatementsA compound statement is formed by combining two or more simple statements A compound statement can be true or false A compound statement involving AND is true when both simple statements are true A compound statement involving OR is true when either one simple statement or both are true
A Complete the truth table
P QP
True or FalseQ
True or FalseP AND Q
True or False
A dog is a mammal Red is a color
A dog is a mammal Red is not a color
A dog is a fish Red is a color
A dog is a fish Red is not a color
B P AND Q is true when
C Complete the truth table
P QP
True or FalseQ
True or FalseP OR Q
True or False
1 is an odd number 2 is an even number
1 is an odd number 2 is an odd number
1 is an even number 2 is an even number
1 is an even number 2 is an odd number
D P OR Q is true when
Reflect
1 Give two simple statements P and Q for which P AND Q is false and P OR Q is true
Module 2 81 Lesson 5
25 Creating and Solving Compound Inequalities
Essential Question How can you solve a compound inequality and graph the solution set
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
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Explain 1 Solving Compound Inequalities Involving ANDCombining two or more simple inequalities forms a compound inequality The graph of a compound inequality involving AND is the intersection or the overlapping region of the simple inequality graphs
Compound Inequalities AND
Words Algebra Graph
All real numbers greater than 2AND less than 6
x gt 2 AND x lt 62 lt x lt 6
All real numbers greater than or equal to 2 AND less than or equal to 6
x ge 2 AND x le 62 le x le 6
Example 1 Solve each compound inequality and graph the solutions
A 4 le x + 2 le 8
4 le x + 2 AND x + 2 le 8 Write the compound inequality using AND
4 - 2 le x + 2 - 2 x + 2 - 2 le 8 - 2 Subtract 2 from both sides of each simple inequality
2 le x x le 6 Simplify
Graph 2 le x
Graph x le 6
Graph the intersection by finding where the two graphs overlap
B -5 le 2x + 3 lt 9
-5 - le 2x + 3 - lt 9 - Subtract from each part of the inequality
le 2x lt Simplify
-8 _ le 2x _ lt 6 _ Divide each part of the inequality by
le x lt Simplify
Graph -4 le x
Graph x lt 3
Graph the intersection by finding where the two graphs overlap -1 0 1 2 3 4 5-5-4 -3 -2
0 2 4 6 8 10 12-8-6-4 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 82 Lesson 5
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Reflect
2 Discussion Explain why 2 le x le 6 can be considered the short method for writing the AND compound inequality x ge 2 AND x le 6
YourTurn
Solve each compound inequality and graph the solutions
3 -2 lt x - 3 lt 5
4 -10 lt 3x + 2 le 8
Explain 2 Solving Compound Inequalities Involving ORThe graph of a compound inequality involving OR is the union or the combined region of the simple inequality graphs
Compound Inequalities OR
Words Algebra Graph
All real numbers less than 2OR greater than 6
x lt 2 OR x gt 6
All real numbers less than or equal to 2OR greater than or equal to 6
x le 2 OR x ge 6
-1 0 1 2 3 4 5-5-4 -3 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 83 Lesson 5
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Example 2 Solve each compound inequality and graph the solutions
A -4 + x gt 1 OR -4 + x lt -3
-4 + x gt 1 OR -4 + x lt -3 Write the compound inequality using OR
-4 + 4 + x gt 1 + 4 -4 + 4 + x lt -3 + 4 Add 4 to both sides of each simple inequality
x gt 5 x lt 1 Simplify
Graph x gt 5
Graph x lt 1
Graph the union by combining the graphs
B 2x le 6 OR 3x gt 12
2x le 6 OR 3x gt 12 Write the compound inequality using OR
2x _ le 6 _ OR 3x _ gt 12 _ Divide the first simple inequality by
x le OR x gt
Graph x le 3
Graph x gt 4
Graph the union by combining the graphs
Reflect
5 Critical Thinking What kind of compound inequality has no solution
Divide the second simple inequality by
Simplify
0 1 2 3 4 5 6-4 -3 -2 -1
-0 1 2 3 4 5 6-4 -3 -2 -1
Module 2 84 Lesson 5
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Your Turn
Solve each compound inequality and graph the solutions
6 x - 5 ge -2 OR x -5 le -6
7 4x -1 lt 15 OR 8x ge 48
Explain 3 Creating Compound Inequalities From GraphsGiven a number line graph with a solution set graphed you can create a compound inequality to fit the graph
Example 3 Write the compound inequality shown by each graph
A
The shaded portion of the graph is not between two values so the compound inequality involves OR
On the left the graph shows an arrow pointing left from -1 and a solid circle so use le
The inequality is x le -1
On the right the graph shows an arrow pointing right from 7 and a solid circle so use ge
The inequality is x ge 7
The compound inequality is x le -1 OR x ge 7
B
The graph is shaded between the values and so the compound inequality involves AND
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The compound inequality is
-1 0 1 2 3 4 5-5-4 -3 -2
4 5 6 7 8 9 100 1 2 3
2 3 4 5 6 7 8-2 -1 0 1
10 2 3 4 5 6 7 8 9-1
Module 2 85 Lesson 5
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oug
hton Mifflin H
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Reflect
8 What is a short method to write the compound inequality x ge 0 AND x lt 6
Your Turn
Write the compound inequality shown by each graph
9
10
Explain 4 Expressing Acceptable Levels with Compound Inequalities
You can express quality-controls levels in real-world problems using compound inequalities
Example 4 Write a compound inequality to represent the indicated quality-control level and graph the solutions
A The recommended pH level for swimming pool water is between 72 and 76 inclusive
Let p be the pH level of swimming pool water
72 is less than or equal to pH level is less than or equal to 76
72 le p le 76
The compound inequality is 72 le p le 76
Graph the solutions
0-10 -8-9 -7-6 -5-4 -3 -2 -1
71 72 73 74 75 76 77 78 79 8070
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 86 Lesson 5
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B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
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oug
hton Mifflin H
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bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
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oug
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Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
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oug
hton Mifflin H
arcourt Publishin
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age C
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Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
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oug
hton
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cour
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pan
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copy
bik
erid
erlo
nd
onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
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oug
hton Mifflin H
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The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
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oug
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pan
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B One moving company charges $800 plus $16 per hour Another moving company charges $720 plus $21 per hour At what number of hours will the charge by both companies be the same What is the charge
Write a verbal description of the basic situation Let t represent the number of hours that the move takes
Moving Charge A plus $16 per hour = Moving Charge B plus $21 per hour
800 + t = 720 + t
800 + t - t = 720 + t - t Subtraction Property of Equality
800 = 720 + t
800 - 720 = 720 + t - 720 Subtraction Property of Equality
= t
_ = t _
Division Property of Equality
t =
The charges are the same for a job that takes hours
Substitute the value 16 in the original equation
800 + 16t = 720 + 21t
800 + 16 ( ) = 720 + 21 ( ) 800 + = 720 +
=
After hours the moving charge for both companies will be
Reflect
6 Suppose you collected the variable terms on the other side of the equal sign to solve the equation Would that affect the solution
Module 2 59 Lesson 2
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hton Mifflin H
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Your Turn
Write and solve an equation to solve each problem7 Claire bought just enough fencing to enclose either a
rectangular garden or a triangular garden as shown The two gardens have the same perimeter How many feet of fencing did she buy
8 A veterinarian is changing the diets of two animals Simba and Cuddles Simba currently consumes 1200 Calories per day That number will increase by 100 Calories each day Cuddles currently consumes 3230 Calories a day That number will decrease by 190 Calories each day The patterns will continue until both animals are consuming the same number of Calories each day In how many days will that be How many Calories will each animal be consuming each day then
Explain 3 Constructing Equations from an Organized TableYou can use a table to organize information and see relationships
Example 3 Construct and solve an equation to solve the problem
Kim works 4 hours more each day than Jill does and Jack works 2 hours less each day than Jill does Over 2 days the number of hours Kim works is equal to the difference of 4 times the number of hours Jack works and the number of hours Jill works How many hours does each person work each day
Analyze Information
Identify the important information
bull Kim works hours more per day than Jill does
bull Jack works hours less per day than Jill does
Formulate a Plan
Make a table using the information given Let x be the number of hours Jill works in one day
Hours Worked Per Day Hours Worked Over 2 Days
Kim
Jill
Jack
Over 2 days the number of hours Kim works is equal to the difference of 4 times the number of hours Jack works and the number of hours Jill works
(3x - 3)(x - 3)
(2x - 1) (2x - 1)
2x
Module 2 60 Lesson 2
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pan
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Solve
2 (x + 4) = 4 2 (x - 2) - 2x
2 (x + 4) = (x - 2) - 2x Simplify
2x + = 8x - - 2x Distributive Property
2x + 8 = x - 16
2x + 8 + = 6x - 16 + Addition Property of Equality
2x + = 6x
2x + 24 - x = 6x - x Subtraction Property of Equality
24 = x
24 _ = x _ Division Property of Equality
= x
Jill works hours per day Kim works hours per day and Jack works
hours per day
Justify and Evaluate
Substitute x = 6 into the original equation
2 (6 + 4) = 4 2 (6 - 2) - 2x
2 ( ) = 8 ( ) - 2 ( ) =
Your Turn
Write and solve an equation to solve the problem
9 Lisa is 10 centimeters taller than her friend Ian Ian is 14 centimeters taller than Jim Every month their heights increase by 2 centimeters In 7 months the sum of Ianrsquos and Jimrsquos heights will be 170 centimeters more than Lisarsquos height How tall is Ian now
Height now Height after 7 months
Module 2 61 Lesson 2
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oug
hton Mifflin H
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Elaborate
10 How can you use properties to solve equations with variables on both sides
11 How is a table helpful when constructing equations
12 When solving a real-world problem to find a personrsquos age would a negative solution make sense Explain
13 Essential Question Check-In How do you write an equation to represent a real-world situation
bull Online Homeworkbull Hints and Helpbull Extra Practice
Write an equation for each description
1 The sum of 14 and a number is equal to 17 2 A number increased by 10 is 114
3 The difference between a number and 12 is 20 4 Ten times the sum of half a number and 6 is 8
5 Two-thirds a number plus 4 is 7 6 Tanmayi wants to raise $175 for a school fundraiser She has raised $120 so far How much more does she need to reach her goal
7 Hector is visiting a cousin who lives 350 miles away He has driven 90 miles How many more miles does he need to drive to reach his cousinrsquos home
8 The length of a rectangle is twice its width The perimeter of the rectangle is 126 feet
Evaluate Homework and Practice
Module 2 62 Lesson 2
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(t)copy
Pete
r K
imS
hutt
erst
ock
Write and solve an equation for each situation
9 In one baseball season Peter hit twice the difference of the number of home runs Alice hit and 6 Altogether they hit 18 home runs How many home runs did each player hit that season
10 The perimeter of a parallelogram is 72 meters The width of the parallelogram is 4 meters less than its length Find the length and the width of the parallelogram
11 One month Ruby worked 6 hours more than Isaac and Svetlana worked 4 times as many hours as Ruby Together they worked 126 hours Find the number of hours each person worked
12 In one day Annie traveled 5 times the sum of the number of hours Brian traveled and 2 Together they traveled 20 hours Find the number of hours each person traveled
13 Xian and his cousin Kai both collect stamps Xian has 56 stamps and Kai has 80 stamps The boys recently joined different stamp-collecting clubs Xianrsquos club will send him 12 new stamps per month Kairsquos club will send him 8 new stamps per month After how many months will Xian and Kai have the same number of stamps How many stamps will each have
14 Kenya plans to make a down payment plus monthly payments in order to buy a motorcycle At one dealer she would pay $2500 down and $150 each month At another dealer she would pay $3000 down and $125 each month After how many months would the total amount paid be the same for both dealers What would that amount be
ℓ meters
(ℓ - 4) meters
Module 2 63 Lesson 2
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oug
hton Mifflin H
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15 Community Gym charges a $50 membership fee and a $55 monthly fee Workout Gym charges a $200 membership fee and a $45 monthly fee After how many months will the total amount of money paid to both gyms be the same What will the amount be
16 Tina is saving to buy a notebook computer She has two options The first option is to put $200 away initially and save $10 every month The second option is to put $100 away initially and save $30 every month After how many months would Tina save the same amount using either option How much would she save with either option
Use the table to answer each question
Starting Salary Yearly Salary Increase
Company A $24000 $3000
Company B $30000 $2400
Company C $36000 $2000
17 After how many years are the salaries offered by Company A and Company B the same
18 After how many years are the salaries offered by Company B and Company C the same
19 Paul started work at Company B ten years ago at the salary shown in the table At the same time Sharla started at Company C at the salary shown in the table Who earned more during the last year How much more
20 Georgersquos page contains twice as many typed words as Billrsquos page and Billrsquos page contains 50 fewer words than Charliersquos page If each person can type 60 words per minute after one minute the difference between twice the number of words on Billrsquos page and the number of words on Charliersquos page is 210 How many words did Billrsquos page contain initially Use a table to organize the information
Initial number of words
Total number of words after one minute
Module 2 64 Lesson 2
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pan
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21 Geometry Sammie bought just enough fencing to border either a rectangular plot or a square plot as shown The perimeters of the plots are the same How many meters of fencing did she buy
HOT Focus on Higher Order Thinking
22 Justify Reasoning Suppose you want to solve the equation 2a + b = 2a where a and b are nonzero real numbers Describe the solution to this equation Justify your description
23 Multi-step A patio in the shape of a rectangle is fenced on all sides with 134 feet of fencing The patio is 5 feet less wide than it is long
a What information can be used to solve the problem How can you find the information
b Describe how to find the area of the patio What is the area of the patio
24 Explain the Error Kevin and Brittany write an equation to represent the following relationship and both students solve their equation Who found the correct equation and solution Why is the other person incorrect
5 times the difference of a number and 20 is the same as half the sum of 4 more than 4 times a number
Kevin Brittany
5 (x - 20) = 1 _ 2 (4x + 4) 5 (20 + x) = 1 _ 2 (4x + 4)
5x - 100 = 2x + 2 100 - 5x = 2x + 2
3x - 100 = 2 100 - 7x = 2
3x = 102 -7x = -98
x = 34 x = 14
(3x + 2) meters
(x + 2) meters
(x + 2) meters
(x - 1) meters
ℓ feet
(ℓ - 5) feet
Module 2 65 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
arcourt Publishin
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pany
25 What If Alexa and Zack are solving the following problem
The number of miles on Car A is 50 miles more than the number of miles on Car B and the number of miles on Car B is 30 miles more than the number of miles on Car C All the cars travel 50 miles in 1 hour After 1 hour twice the number of miles on Car A is 70 miles less than 3 times the number of miles on Car C How many miles were there on Car B initially
Alexa assumes there are m miles on Car B Zack assumes there are m miles on Car C Will Zackrsquos answer be the same as Alexarsquos answer Explain
Lesson Performance Task
Stacy Oliver and Jivesh each plan to put a certain amount of money into their savings accounts that earn simple interest of 6 per year Stacy puts $550 more than Jivesh and Oliver puts in 2 times as much as Jivesh After a year the amount in Stacyrsquos account is 2 times the sum of $212 and the amount in Oliverrsquos account How much does each person initially put into his or her account Who had the most money in his or her account after a year Who had the least Explain
Zackrsquos Table Initial Miles
Miles after One Hour
Alexarsquos Table Initial Miles
Miles after One Hour
Amount in Account Initially Amount in Account after One Year
Module 2 66 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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Har
cour
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lishi
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pan
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Name Class Date
Resource Locker
Explore Rearranging Mathematical FormulasLiteral Equations are equations that contain two or more variables There are many literal equations in the form of math science and engineering formulas These formulas may seem like they can only be solved for the variable that is isolated on one side of the formula By using inverse operations and the properties of equality a formula can be rearranged so any variable in the formula can be isolated It is no different than how equations are solved by using inverse operations and the properties of equality
How can you solve the equation 42 = 6x
A42 _ = 6x _ What is the reason for dividing
Why divide by
= x By rearranging the equation x was isolated and the solution was found
The mathematical formula for the volume of a rectangular prism B = Vh or V = ℓwh is a literal equation V represents volume ℓ represents length w represents width and h represents height Using inverse operations the formula can be rearranged to solve for any one of the variables that might be unknown Like solving for x a formula can be rearranged to isolate a variable
B In the formula V = ℓwh the variable h needs to be isolated
The operation of is used in the formula The inverse
operation should be used
to isolate
C V _____ = ℓwh _____
V _ =
The formula rearranged in this way can easily produce the height of the rectangular prism when the volume length and width are known
Reflect
1 Using the formula for a rectangular prism rewrite the formula to solve for ℓ
ℓw
h
Module 2 67 Lesson 3
23 Solving for a VariableEssential Question How do you rewrite formulas and literal equations
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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arcourt Publishin
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age C
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Photo
grap
hyAurora Ph
otosCorb
is
Explain 1 Rearranging Scientific FormulasUse inverse operations to isolate the unknown variable in a scientific formula
The formula for density is D = m __ V Lead has a very high density of 11340 kg m 3 Plastic foam has a very low density of 75 kg m 3 The formula for density can be rearranged to solve for V volume or m mass
Example 1
A A sinker on a fishing line is made of lead and has a volume of 0000015 m 3 What is the mass of the sinker
The density formula can be rearranged to isolate m the mass The values for volume and density can then be substituted into the formula to find the mass
D = m _ V
DV = ( m _ V ) V DV = m
(11340 kg m 3 ) (0000015 m 3 ) = m
017 kg asymp m
B The design for a life preserver requires 03 kilogram of plastic foam to provide proper buoyancy What is the volume of the plastic foam required
Rearrange the density formula to isolate V
D = m _ V
(D) V = m _ V
DV =
DV _ = m _
V =
Now substitute the given values
V = _
V = m 3
Your Turn
2 For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Determine the altitude in feet when t is -275 ∘F and g is 60 ∘F
Module 2 68 Lesson 3
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
copy H
oug
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Mif
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Har
cour
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lishi
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Com
pan
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Explain 2 Rearranging Literal EquationsUsing inverse operations to rearrange literal equations can be applied to any formula The interest formula I = prt is another example of a literal equation In the formula I represents interest p the principal or the initial amount to which interest will be applied r the rate at which interest will be paid and t is the time in years
Example 2
A Find the number of years used in the calculation of a $1000 loan at an interest rate of 5 with interest totaling $600
Solve the formula for t
I = prt
I _ pr = prt
_ pr
I _ pr = t
Substitute the given values Since the interest rate is 5 r = 005$600 __
$1000 middot 005 = t
12 = t
So the length of time for the loan is 12 years
B Determine the interest rate for a $2000 loan that will be paid off in 4 years with interest totaling $640 In order to find the interest rate solve the formula for r
I = prt
I _ = prt _
_ = r
Now substitute the values and simplify
__
( ) ( ) = r
008 = r
So the interest rate is per year
Your Turn
3 The formula y = mx + b is the slope-intercept form of the equation of a line Solve the equation for m
Module 2 69 Lesson 3
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pany
bull Online Homeworkbull Hints and Helpbull Extra Practice
Solve for the indicated variable in each mathematical formula
1 C = 2πr for r 2 A = 1 __ 2 bh for b 3 y = mx + b for x
4 A = 1 __ 2 (a + b)h for h 5 V = πr2h for h 6 SA = 2πr2 + 2πrh for h
Solve for the indicated variable in each scientific formula
7 d = rt for t 8 PV = nRT for T
9 A = FV - OV _______ T for OV 10 C = Wtc _ 1000 for W
Evaluate Homework and Practice
Elaborate
4 Discussion What could be a reason for isolating a variable in a literal equation
5 Describe a situation in which a formula could be used more easily if it were rearranged Include the formula in your description
6 Essential Question Check-In How do you isolate a variable
Module 2 70 Lesson 3
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cean
C
orb
is
Solve for the indicated variable in each literal equation
11 2p + 5r = q for p 12 -10 = xy + z for x 13 a __ b = c for b
14 h - 4 _ j = k for j 15 x __ 5 - g = a for x 16 5p + 9c = p for c
17 2 __ 5 (z + 1) = y for z 18 g (h + 2 __ 3 ) = 1 for h 19 a(n - 3) + 8 = bn for n
20 Which is a possible way to rewrite the equation y = 3x + 3b to solve for b
A b = y - 3x
_ 3 C b = y - 3
_____ 3x
B b = 3(y - 3x) D b = x(y - 3)
21 Sports To find a baseball pitcherrsquos earned run average (ERA) you can use the formula Ei = 9r in which E represents ERA i represents the number of innings pitched and r represents the number of earned runs allowed Solve the equation for E What is a pitcherrsquos ERA if he allows 5 earned runs in 18 innings pitched
22 Meteorology For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Solve the equation for a If the atmospheric temperature is -655 ∘F and the ground temperature is 57 ∘F what is the altitude
Module 2 71 Lesson 3
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Rand
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aineA
lamy
HOT Focus on Higher Order Thinking
23 Explain the Error A student was asked to use the formula for the perimeter of a rectangle P = 2ℓ + 2w to solve for ℓ The student came up with an answer P - 2w = 2ℓ What error did the student make Explain Then solve for ℓ
24 Multi-Step The formula c = 5p + 215 relates c the total cost in dollars of hosting a birthday party at a skating rink to p the number of people attending If Alliersquos parents are willing to spend $300 for a party how many people can attend
25 Multi-Step The formula for the area of a triangle is A = 1 __ 2 bh in which b represents the length of thebase and h represents the height If a triangle has an area of 192 mm2 and the height is 12 mm what is the measure of the base
Lesson Performance TaskThe following table shows the average low temperatures in Fahrenheit for the city of Boston for several months during the year The formula F = 9 __ 5 C + 32 allows you to determine the temperature in Fahrenheit when given the temperature in Celsius
MonthTemperature in
FahrenheitTemperature in
Celsius
January 22deg
April 41deg
July 65deg
October 47deg
December 28deg
a Use the information given to determine the average low temperatures in Celsius
b Would it ever be possible for the temperature in Celsius to have a greater value than the temperature in Fahrenheit Explain why or why not
Module 2 72 Lesson 3
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Name Class Date
Resource Locker
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oug
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Mif
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Har
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Com
pan
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mag
e cr
edit
s copy
Patr
ick
Lan
eSo
mos
Imag
esC
orb
is
Explore Creating Inequalities from Verbal DescriptionsAn inequality is a statement that compares two expressions that are not strictly equal by using one of the following inequality signs
Symbol Meaning
lt is less than
le is less than or equal to
gt is greater than
ge is greater than or equal to
ne is not equal to
You have probably seen a sign at an amusement park saying something like ldquoYou must be at least 48 inches tall to ride this riderdquo This statement could be written as h ge 48 in where h represents the height of a person allowed to ride
Nora is planning a birthday party for her little sister Colleen Norarsquos budget will allow her to spend no more than $50 for party supplies Eight children including Colleen will attend the party and Nora wants to determine how much she could spend on party favors for each child She will also purchase a cake for $10 Write an inequality that represents the situation and find possible solutions
A First let c represent the cost of a party favor for each child Write an expression for the total cost of the party as a function of c
c +
B Which inequality symbol should be used to represent the phrase ldquono more thanrdquo
C Write the inequality that represents Norarsquos budget goal
8c + 10 le
D Suppose Nora finds party favors that cost $4 each Use a value of 4 for c and check to see if this inequality is true
8 middot 4 + 10 le 50
le 50
Module 2 73 Lesson 4
24 Creating and Solving Inequalities
Essential Question How do you write and solve an inequality that represents a real-world situation
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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pany
Is the inequality true
Could Nora buy $6 party favors for all of her guests without going over budget
Reflect
1 Why does an inequality represent Norarsquos budget calculation better than an equation
2 The solution set of an inequality consists of all values that make the statement true Describe the whole dollar amounts that are in the solution set for this situation
Explain 1 Creating and Solving Inequalities Involving the Distributive Property
You may need to use the Distributive Property before you can solve an inequality
Distributive Property If a b and c are real numbers then a(b + c) = ab + ac
The inequality sign must be reversed when multiplying or dividing both sides of an inequality by a negative number
Example 1
A Trina is buying 12 shirts for the drama club She will choose a style for the blank shirts and then pay an additional charge of $275 for each shirt to have the club logo If Trina cannot spend more than $99 how much can she spend on each blank shirt Write and solve an inequality to find the possible cost of each blank shirt
Let s represent the cost of each blank shirt
Write an inequality to represent the situation 12(s + 275) le 99
Use the Distributive Property 12s + 33 le 99
Subtraction Property of Inequality 12s + 33 - 33 le 99 - 33
Simplify 12s le 66
Division Property of Inequality 12s ___ 12 le 66 __ 12
Simplify s le 55
Module 2 74 Lesson 4
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Check your answer
Since s le 55 check a smaller number 12(5 + 275) le 99
Trina can order blank shirts that cost $550 or less 93 le 99 true
B Sergio needs to buy gifts for 8 friends He wants to give the same gift to all his friends and he plans to have the gifts wrapped for an additional charge of $150 each If Sergio spends at least $70 he will receive free shipping on his order Write and solve an inequality to determine how much Sergio needs to spend on each gift in order to receive free shipping
Let g be the cost of one gift
Write an inequality to represent the situation ( g + ) ge 70
Use the Distributive Property g + ge 70
Subtraction Property of Inequality g + 12 - ge 70 -
Simplify 8g ge
Division Property of Inequality 8g _
ge 58 _
Simplify g ge
Check your answer
Since g ge 725 check a larger number 8(8 + 150) ge 70
Sergio must spend at least on each gift ge 70
Reflect
3 Discussion Why is the first step in solving the inequality to use the Distributive Property instead of working inside the parentheses
Your Turn
4 Zachary is planning to send a video game to each of his two brothers If he buys the same game for both brothers and pays $475 to ship each game how much can he spend on each game without spending more than $100 Write and solve an inequality for this situation
Solve each inequality
5 4 _ 3 (6x + 9) lt 4 6 -2 ( 1 _ 4 x + 2 ) ge 5
Module 2 75 Lesson 4
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Explain 2 Creating and Solving Inequalities with Variables on Both Sides
Some inequalities have variable terms on both sides of the inequality symbol You can solve these inequalities the same way you solved equations with variables on both sides Use the properties of inequality to collect all the variable terms on one side and all the constant terms on the other side
Example 2
A The Daily Info charges a fee of $650 plus $80 per week to run an ad The Peoplersquos Paper charges $145 per week For how many weeks must an ad run for the total cost at the Daily Info to be less expensive than the cost at the Peoplersquos Paper Let w be the number of weeks the ad runs in the paper
Write an inequality to represent the situation 650 + 80w lt 145w
Subtraction Property of Inequality 650 + 80w - 80w lt 145w - 80w
Simplify 650 lt 65w
Division Property of Inequality 650 _ 65 lt 65w _ 65
Simplify 10 lt w
The total cost at the Daily Info is less than the cost at the Peoplersquos Paper if the ad runs for more than 10 weeks
B The Home Cleaning Company charges $312 to power-wash the siding of a house plus $12 for each window Power Clean charges $36 per window and the price includes power-washing the siding How many windows must a house have to make the total cost from The Home Cleaning Company less expensive than Power Clean Let w be the number of windows
Write an inequality to represent the situation +12w lt 36w
Subtraction Property of Inequality 312 + 12w - lt 36w -
Simplify 312 lt
Division Property of Inequality 312 _ lt 24w _
Simplify lt w
A house must have more than 13 windows for The Home Cleaning Company to be less expensive than Power Clean
Reflect
7 How would the final inequality change if you divided by ndash24 in the next to last step
Your Turn
8 The school band will sell pizzas to raise money for new uniforms The supplier charges $100 plus $4 per pizza The band members sell the pizzas for $7 each Write and solve an inequality to find how many pizzas the band members will have to sell to make a profit
Module 2 76 Lesson 4
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Elaborate
9 Which inequality symbol would you use to represent the following words or phrases Can you come up with more examples
a at most b farther than c younger than d up to
10 Discussion How are the steps to solving an inequality similar to those for solving an equation How are they different
11 Essential Question Check-In How can you write an inequality that represents a real-world situation
Write an inequality that represents the description and then solve
1 Max has more than 5 carrots (number of carrots Max has = c)
2 Brigitte is shorter than 5 feet (Brigittersquos height = h)
3 Twice a number (x) is less than 10 4 Six more than five times a number (x) is at least twenty-one
5 Dave has $15 to spend on an $8 book and two birthday cards (c) for his friends How much can he spend on each card if he buys the same card for each friend
6 Toni can carry up to 18 lb in her backpack Her lunch weighs 1 lb her gym clothes weigh 2 lb and her books (b) weigh 3 lb each How many books can she carry in her backpack
Evaluate Homework and Practice
bull Online Homeworkbull Hints and Helpbull Extra Practice
Module 2 77 Lesson 4
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pany
Solve each inequality
7 3 (x - 2) gt -3 8 5 + 5 (x + 4) le 20 9 3 + 1 _ 2 (3 - x) lt -7
10 3 (x + 6) - 2 (x + 2) ge 10 11 5 (3 - x) -4 (2 - 3x) gt 2 12 1 _ 2 (4x - 2) - 2 _ 3 (6x + 9) le 4
13 x + 1 gt -5 (7 - 2x) 14 5 _ 3 (6x + 3) le 2x - 7
15 2x le - 2 __ 3 (4x + 4) 16 1 __ 2 (-2x - 10) gt 3 (4 - 6x)
17 -5 - 3x ge 2 (10 + 2x) + 3 18 -3 (9x + 20) ge 15x - 20
19 8 ( 1 _ 4 x - 3) + 24 lt 4 ( x + 5 ) 20 6x - 2 (x + 2) gt 2 - 3 (x + 3)
Module 2 78 Lesson 4
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21 Physics A crane cable can support a maximum load of 15000 kg If a bucket has a mass of 2000 kg and gravel has a mass of 1500 kg for every cubic meter how many cubic meters of gravel (g) can be safely lifted by the crane
22 Find the solution set of each inequality below and then determine which inequalities have the same solution set as 1 _ 3 ( -5x - 3 ) lt 14
a 1 _ 3 (5x + 3) gt -14 b 2 _ 5 (10x + 20) gt 44
c - 2 _ 5 (10x + 20) lt -44 d - 1 _ 3 (5x + 3) lt 14
e 2 _ 5 (10x - 20) gt -44 f 1 _ 3 (5x + 3) lt -14
HOT Focus on Higher Order Thinking
23 Explain the Error Sven is trying to find the maximum amount of time he can spend practicing the five scales of piano music he is supposed to be working on He has 60 minutes to practice piano and would like to spend at least 35 minutes playing songs instead of practicing scales So Sven sets up the following inequality where t is the number of minutes he spends on each scale and solves it
60 - 5t le 35-5t le -25
t ge 5
Sven has concluded that he should spend 5 minutes or more on each scale Is this correct If not what mistake did he make Then solve for the correct answer
Module 2 79 Lesson 4
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24 Critical Thinking Anika wants to determine the maximum number of tulip bulbs (t) she can purchase if each bulb costs $150 She will also need to purchase separate pots for each bulb at $125 each and a bag of potting soil for $1000 Set up an inequality to determine how many tulip bulbs Anika can purchase without spending more than $2000 and solve it Can Anika buy exactly enough bulbs and pots to spend the full $2000 Explain Can you think of a better inequality to describe the answer
25 Geometry The area of the triangle shown is no more than 10 square inches
a Write an inequality that can be used to find x
b Solve the inequality from part a c What is the maximum height of the triangle
Lesson Performance TaskWhen planning an airplane route the trip planner must be careful to consider the range the aircraft can travel and the availability of airports to stop and refuel
A large commercial jet airplane burns approximately 5 gallons of fuel per mile flown plus about 8500 gallons of fuel per trip to reach cruising altitude With a useable fuel capacity of 50000 gallons (there is additional fuel reserved for emergencies) describe the acceptable distance for which an airline could establish a non-stop flight
For flights originating from Chicago determine which cities could be safely reached by a non-stop flight
City Distance from Chicago (miles)
Bangalore India 8530
Jakarta Indonesia 9810
Johannesburg South Africa 8680
Moscow Russia 4970
Paris France 4130
Perth Australia 10970
Tokyo Japan 6300
copy H
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its copySarych
eva O
lesiaShutterstock
(2x - 3) in
4 in
Module 2 80 Lesson 4
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Name Class Date
Resource Locker
Explore Truth Tables and Compound StatementsA compound statement is formed by combining two or more simple statements A compound statement can be true or false A compound statement involving AND is true when both simple statements are true A compound statement involving OR is true when either one simple statement or both are true
A Complete the truth table
P QP
True or FalseQ
True or FalseP AND Q
True or False
A dog is a mammal Red is a color
A dog is a mammal Red is not a color
A dog is a fish Red is a color
A dog is a fish Red is not a color
B P AND Q is true when
C Complete the truth table
P QP
True or FalseQ
True or FalseP OR Q
True or False
1 is an odd number 2 is an even number
1 is an odd number 2 is an odd number
1 is an even number 2 is an even number
1 is an even number 2 is an odd number
D P OR Q is true when
Reflect
1 Give two simple statements P and Q for which P AND Q is false and P OR Q is true
Module 2 81 Lesson 5
25 Creating and Solving Compound Inequalities
Essential Question How can you solve a compound inequality and graph the solution set
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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Explain 1 Solving Compound Inequalities Involving ANDCombining two or more simple inequalities forms a compound inequality The graph of a compound inequality involving AND is the intersection or the overlapping region of the simple inequality graphs
Compound Inequalities AND
Words Algebra Graph
All real numbers greater than 2AND less than 6
x gt 2 AND x lt 62 lt x lt 6
All real numbers greater than or equal to 2 AND less than or equal to 6
x ge 2 AND x le 62 le x le 6
Example 1 Solve each compound inequality and graph the solutions
A 4 le x + 2 le 8
4 le x + 2 AND x + 2 le 8 Write the compound inequality using AND
4 - 2 le x + 2 - 2 x + 2 - 2 le 8 - 2 Subtract 2 from both sides of each simple inequality
2 le x x le 6 Simplify
Graph 2 le x
Graph x le 6
Graph the intersection by finding where the two graphs overlap
B -5 le 2x + 3 lt 9
-5 - le 2x + 3 - lt 9 - Subtract from each part of the inequality
le 2x lt Simplify
-8 _ le 2x _ lt 6 _ Divide each part of the inequality by
le x lt Simplify
Graph -4 le x
Graph x lt 3
Graph the intersection by finding where the two graphs overlap -1 0 1 2 3 4 5-5-4 -3 -2
0 2 4 6 8 10 12-8-6-4 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 82 Lesson 5
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Reflect
2 Discussion Explain why 2 le x le 6 can be considered the short method for writing the AND compound inequality x ge 2 AND x le 6
YourTurn
Solve each compound inequality and graph the solutions
3 -2 lt x - 3 lt 5
4 -10 lt 3x + 2 le 8
Explain 2 Solving Compound Inequalities Involving ORThe graph of a compound inequality involving OR is the union or the combined region of the simple inequality graphs
Compound Inequalities OR
Words Algebra Graph
All real numbers less than 2OR greater than 6
x lt 2 OR x gt 6
All real numbers less than or equal to 2OR greater than or equal to 6
x le 2 OR x ge 6
-1 0 1 2 3 4 5-5-4 -3 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 83 Lesson 5
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Example 2 Solve each compound inequality and graph the solutions
A -4 + x gt 1 OR -4 + x lt -3
-4 + x gt 1 OR -4 + x lt -3 Write the compound inequality using OR
-4 + 4 + x gt 1 + 4 -4 + 4 + x lt -3 + 4 Add 4 to both sides of each simple inequality
x gt 5 x lt 1 Simplify
Graph x gt 5
Graph x lt 1
Graph the union by combining the graphs
B 2x le 6 OR 3x gt 12
2x le 6 OR 3x gt 12 Write the compound inequality using OR
2x _ le 6 _ OR 3x _ gt 12 _ Divide the first simple inequality by
x le OR x gt
Graph x le 3
Graph x gt 4
Graph the union by combining the graphs
Reflect
5 Critical Thinking What kind of compound inequality has no solution
Divide the second simple inequality by
Simplify
0 1 2 3 4 5 6-4 -3 -2 -1
-0 1 2 3 4 5 6-4 -3 -2 -1
Module 2 84 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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Your Turn
Solve each compound inequality and graph the solutions
6 x - 5 ge -2 OR x -5 le -6
7 4x -1 lt 15 OR 8x ge 48
Explain 3 Creating Compound Inequalities From GraphsGiven a number line graph with a solution set graphed you can create a compound inequality to fit the graph
Example 3 Write the compound inequality shown by each graph
A
The shaded portion of the graph is not between two values so the compound inequality involves OR
On the left the graph shows an arrow pointing left from -1 and a solid circle so use le
The inequality is x le -1
On the right the graph shows an arrow pointing right from 7 and a solid circle so use ge
The inequality is x ge 7
The compound inequality is x le -1 OR x ge 7
B
The graph is shaded between the values and so the compound inequality involves AND
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The compound inequality is
-1 0 1 2 3 4 5-5-4 -3 -2
4 5 6 7 8 9 100 1 2 3
2 3 4 5 6 7 8-2 -1 0 1
10 2 3 4 5 6 7 8 9-1
Module 2 85 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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Reflect
8 What is a short method to write the compound inequality x ge 0 AND x lt 6
Your Turn
Write the compound inequality shown by each graph
9
10
Explain 4 Expressing Acceptable Levels with Compound Inequalities
You can express quality-controls levels in real-world problems using compound inequalities
Example 4 Write a compound inequality to represent the indicated quality-control level and graph the solutions
A The recommended pH level for swimming pool water is between 72 and 76 inclusive
Let p be the pH level of swimming pool water
72 is less than or equal to pH level is less than or equal to 76
72 le p le 76
The compound inequality is 72 le p le 76
Graph the solutions
0-10 -8-9 -7-6 -5-4 -3 -2 -1
71 72 73 74 75 76 77 78 79 8070
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 86 Lesson 5
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B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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pany
bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
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Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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age C
redits copy
Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
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bik
erid
erlo
nd
onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
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The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
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Your Turn
Write and solve an equation to solve each problem7 Claire bought just enough fencing to enclose either a
rectangular garden or a triangular garden as shown The two gardens have the same perimeter How many feet of fencing did she buy
8 A veterinarian is changing the diets of two animals Simba and Cuddles Simba currently consumes 1200 Calories per day That number will increase by 100 Calories each day Cuddles currently consumes 3230 Calories a day That number will decrease by 190 Calories each day The patterns will continue until both animals are consuming the same number of Calories each day In how many days will that be How many Calories will each animal be consuming each day then
Explain 3 Constructing Equations from an Organized TableYou can use a table to organize information and see relationships
Example 3 Construct and solve an equation to solve the problem
Kim works 4 hours more each day than Jill does and Jack works 2 hours less each day than Jill does Over 2 days the number of hours Kim works is equal to the difference of 4 times the number of hours Jack works and the number of hours Jill works How many hours does each person work each day
Analyze Information
Identify the important information
bull Kim works hours more per day than Jill does
bull Jack works hours less per day than Jill does
Formulate a Plan
Make a table using the information given Let x be the number of hours Jill works in one day
Hours Worked Per Day Hours Worked Over 2 Days
Kim
Jill
Jack
Over 2 days the number of hours Kim works is equal to the difference of 4 times the number of hours Jack works and the number of hours Jill works
(3x - 3)(x - 3)
(2x - 1) (2x - 1)
2x
Module 2 60 Lesson 2
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pan
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Solve
2 (x + 4) = 4 2 (x - 2) - 2x
2 (x + 4) = (x - 2) - 2x Simplify
2x + = 8x - - 2x Distributive Property
2x + 8 = x - 16
2x + 8 + = 6x - 16 + Addition Property of Equality
2x + = 6x
2x + 24 - x = 6x - x Subtraction Property of Equality
24 = x
24 _ = x _ Division Property of Equality
= x
Jill works hours per day Kim works hours per day and Jack works
hours per day
Justify and Evaluate
Substitute x = 6 into the original equation
2 (6 + 4) = 4 2 (6 - 2) - 2x
2 ( ) = 8 ( ) - 2 ( ) =
Your Turn
Write and solve an equation to solve the problem
9 Lisa is 10 centimeters taller than her friend Ian Ian is 14 centimeters taller than Jim Every month their heights increase by 2 centimeters In 7 months the sum of Ianrsquos and Jimrsquos heights will be 170 centimeters more than Lisarsquos height How tall is Ian now
Height now Height after 7 months
Module 2 61 Lesson 2
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oug
hton Mifflin H
arcourt Publishin
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pany
Elaborate
10 How can you use properties to solve equations with variables on both sides
11 How is a table helpful when constructing equations
12 When solving a real-world problem to find a personrsquos age would a negative solution make sense Explain
13 Essential Question Check-In How do you write an equation to represent a real-world situation
bull Online Homeworkbull Hints and Helpbull Extra Practice
Write an equation for each description
1 The sum of 14 and a number is equal to 17 2 A number increased by 10 is 114
3 The difference between a number and 12 is 20 4 Ten times the sum of half a number and 6 is 8
5 Two-thirds a number plus 4 is 7 6 Tanmayi wants to raise $175 for a school fundraiser She has raised $120 so far How much more does she need to reach her goal
7 Hector is visiting a cousin who lives 350 miles away He has driven 90 miles How many more miles does he need to drive to reach his cousinrsquos home
8 The length of a rectangle is twice its width The perimeter of the rectangle is 126 feet
Evaluate Homework and Practice
Module 2 62 Lesson 2
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Pete
r K
imS
hutt
erst
ock
Write and solve an equation for each situation
9 In one baseball season Peter hit twice the difference of the number of home runs Alice hit and 6 Altogether they hit 18 home runs How many home runs did each player hit that season
10 The perimeter of a parallelogram is 72 meters The width of the parallelogram is 4 meters less than its length Find the length and the width of the parallelogram
11 One month Ruby worked 6 hours more than Isaac and Svetlana worked 4 times as many hours as Ruby Together they worked 126 hours Find the number of hours each person worked
12 In one day Annie traveled 5 times the sum of the number of hours Brian traveled and 2 Together they traveled 20 hours Find the number of hours each person traveled
13 Xian and his cousin Kai both collect stamps Xian has 56 stamps and Kai has 80 stamps The boys recently joined different stamp-collecting clubs Xianrsquos club will send him 12 new stamps per month Kairsquos club will send him 8 new stamps per month After how many months will Xian and Kai have the same number of stamps How many stamps will each have
14 Kenya plans to make a down payment plus monthly payments in order to buy a motorcycle At one dealer she would pay $2500 down and $150 each month At another dealer she would pay $3000 down and $125 each month After how many months would the total amount paid be the same for both dealers What would that amount be
ℓ meters
(ℓ - 4) meters
Module 2 63 Lesson 2
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oug
hton Mifflin H
arcourt Publishin
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pany
15 Community Gym charges a $50 membership fee and a $55 monthly fee Workout Gym charges a $200 membership fee and a $45 monthly fee After how many months will the total amount of money paid to both gyms be the same What will the amount be
16 Tina is saving to buy a notebook computer She has two options The first option is to put $200 away initially and save $10 every month The second option is to put $100 away initially and save $30 every month After how many months would Tina save the same amount using either option How much would she save with either option
Use the table to answer each question
Starting Salary Yearly Salary Increase
Company A $24000 $3000
Company B $30000 $2400
Company C $36000 $2000
17 After how many years are the salaries offered by Company A and Company B the same
18 After how many years are the salaries offered by Company B and Company C the same
19 Paul started work at Company B ten years ago at the salary shown in the table At the same time Sharla started at Company C at the salary shown in the table Who earned more during the last year How much more
20 Georgersquos page contains twice as many typed words as Billrsquos page and Billrsquos page contains 50 fewer words than Charliersquos page If each person can type 60 words per minute after one minute the difference between twice the number of words on Billrsquos page and the number of words on Charliersquos page is 210 How many words did Billrsquos page contain initially Use a table to organize the information
Initial number of words
Total number of words after one minute
Module 2 64 Lesson 2
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oug
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cour
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pan
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21 Geometry Sammie bought just enough fencing to border either a rectangular plot or a square plot as shown The perimeters of the plots are the same How many meters of fencing did she buy
HOT Focus on Higher Order Thinking
22 Justify Reasoning Suppose you want to solve the equation 2a + b = 2a where a and b are nonzero real numbers Describe the solution to this equation Justify your description
23 Multi-step A patio in the shape of a rectangle is fenced on all sides with 134 feet of fencing The patio is 5 feet less wide than it is long
a What information can be used to solve the problem How can you find the information
b Describe how to find the area of the patio What is the area of the patio
24 Explain the Error Kevin and Brittany write an equation to represent the following relationship and both students solve their equation Who found the correct equation and solution Why is the other person incorrect
5 times the difference of a number and 20 is the same as half the sum of 4 more than 4 times a number
Kevin Brittany
5 (x - 20) = 1 _ 2 (4x + 4) 5 (20 + x) = 1 _ 2 (4x + 4)
5x - 100 = 2x + 2 100 - 5x = 2x + 2
3x - 100 = 2 100 - 7x = 2
3x = 102 -7x = -98
x = 34 x = 14
(3x + 2) meters
(x + 2) meters
(x + 2) meters
(x - 1) meters
ℓ feet
(ℓ - 5) feet
Module 2 65 Lesson 2
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oug
hton Mifflin H
arcourt Publishin
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25 What If Alexa and Zack are solving the following problem
The number of miles on Car A is 50 miles more than the number of miles on Car B and the number of miles on Car B is 30 miles more than the number of miles on Car C All the cars travel 50 miles in 1 hour After 1 hour twice the number of miles on Car A is 70 miles less than 3 times the number of miles on Car C How many miles were there on Car B initially
Alexa assumes there are m miles on Car B Zack assumes there are m miles on Car C Will Zackrsquos answer be the same as Alexarsquos answer Explain
Lesson Performance Task
Stacy Oliver and Jivesh each plan to put a certain amount of money into their savings accounts that earn simple interest of 6 per year Stacy puts $550 more than Jivesh and Oliver puts in 2 times as much as Jivesh After a year the amount in Stacyrsquos account is 2 times the sum of $212 and the amount in Oliverrsquos account How much does each person initially put into his or her account Who had the most money in his or her account after a year Who had the least Explain
Zackrsquos Table Initial Miles
Miles after One Hour
Alexarsquos Table Initial Miles
Miles after One Hour
Amount in Account Initially Amount in Account after One Year
Module 2 66 Lesson 2
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oug
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pan
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Name Class Date
Resource Locker
Explore Rearranging Mathematical FormulasLiteral Equations are equations that contain two or more variables There are many literal equations in the form of math science and engineering formulas These formulas may seem like they can only be solved for the variable that is isolated on one side of the formula By using inverse operations and the properties of equality a formula can be rearranged so any variable in the formula can be isolated It is no different than how equations are solved by using inverse operations and the properties of equality
How can you solve the equation 42 = 6x
A42 _ = 6x _ What is the reason for dividing
Why divide by
= x By rearranging the equation x was isolated and the solution was found
The mathematical formula for the volume of a rectangular prism B = Vh or V = ℓwh is a literal equation V represents volume ℓ represents length w represents width and h represents height Using inverse operations the formula can be rearranged to solve for any one of the variables that might be unknown Like solving for x a formula can be rearranged to isolate a variable
B In the formula V = ℓwh the variable h needs to be isolated
The operation of is used in the formula The inverse
operation should be used
to isolate
C V _____ = ℓwh _____
V _ =
The formula rearranged in this way can easily produce the height of the rectangular prism when the volume length and width are known
Reflect
1 Using the formula for a rectangular prism rewrite the formula to solve for ℓ
ℓw
h
Module 2 67 Lesson 3
23 Solving for a VariableEssential Question How do you rewrite formulas and literal equations
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oug
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Photo
grap
hyAurora Ph
otosCorb
is
Explain 1 Rearranging Scientific FormulasUse inverse operations to isolate the unknown variable in a scientific formula
The formula for density is D = m __ V Lead has a very high density of 11340 kg m 3 Plastic foam has a very low density of 75 kg m 3 The formula for density can be rearranged to solve for V volume or m mass
Example 1
A A sinker on a fishing line is made of lead and has a volume of 0000015 m 3 What is the mass of the sinker
The density formula can be rearranged to isolate m the mass The values for volume and density can then be substituted into the formula to find the mass
D = m _ V
DV = ( m _ V ) V DV = m
(11340 kg m 3 ) (0000015 m 3 ) = m
017 kg asymp m
B The design for a life preserver requires 03 kilogram of plastic foam to provide proper buoyancy What is the volume of the plastic foam required
Rearrange the density formula to isolate V
D = m _ V
(D) V = m _ V
DV =
DV _ = m _
V =
Now substitute the given values
V = _
V = m 3
Your Turn
2 For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Determine the altitude in feet when t is -275 ∘F and g is 60 ∘F
Module 2 68 Lesson 3
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cour
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Explain 2 Rearranging Literal EquationsUsing inverse operations to rearrange literal equations can be applied to any formula The interest formula I = prt is another example of a literal equation In the formula I represents interest p the principal or the initial amount to which interest will be applied r the rate at which interest will be paid and t is the time in years
Example 2
A Find the number of years used in the calculation of a $1000 loan at an interest rate of 5 with interest totaling $600
Solve the formula for t
I = prt
I _ pr = prt
_ pr
I _ pr = t
Substitute the given values Since the interest rate is 5 r = 005$600 __
$1000 middot 005 = t
12 = t
So the length of time for the loan is 12 years
B Determine the interest rate for a $2000 loan that will be paid off in 4 years with interest totaling $640 In order to find the interest rate solve the formula for r
I = prt
I _ = prt _
_ = r
Now substitute the values and simplify
__
( ) ( ) = r
008 = r
So the interest rate is per year
Your Turn
3 The formula y = mx + b is the slope-intercept form of the equation of a line Solve the equation for m
Module 2 69 Lesson 3
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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oug
hton Mifflin H
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pany
bull Online Homeworkbull Hints and Helpbull Extra Practice
Solve for the indicated variable in each mathematical formula
1 C = 2πr for r 2 A = 1 __ 2 bh for b 3 y = mx + b for x
4 A = 1 __ 2 (a + b)h for h 5 V = πr2h for h 6 SA = 2πr2 + 2πrh for h
Solve for the indicated variable in each scientific formula
7 d = rt for t 8 PV = nRT for T
9 A = FV - OV _______ T for OV 10 C = Wtc _ 1000 for W
Evaluate Homework and Practice
Elaborate
4 Discussion What could be a reason for isolating a variable in a literal equation
5 Describe a situation in which a formula could be used more easily if it were rearranged Include the formula in your description
6 Essential Question Check-In How do you isolate a variable
Module 2 70 Lesson 3
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Mif
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cour
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pan
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mag
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copyO
cean
C
orb
is
Solve for the indicated variable in each literal equation
11 2p + 5r = q for p 12 -10 = xy + z for x 13 a __ b = c for b
14 h - 4 _ j = k for j 15 x __ 5 - g = a for x 16 5p + 9c = p for c
17 2 __ 5 (z + 1) = y for z 18 g (h + 2 __ 3 ) = 1 for h 19 a(n - 3) + 8 = bn for n
20 Which is a possible way to rewrite the equation y = 3x + 3b to solve for b
A b = y - 3x
_ 3 C b = y - 3
_____ 3x
B b = 3(y - 3x) D b = x(y - 3)
21 Sports To find a baseball pitcherrsquos earned run average (ERA) you can use the formula Ei = 9r in which E represents ERA i represents the number of innings pitched and r represents the number of earned runs allowed Solve the equation for E What is a pitcherrsquos ERA if he allows 5 earned runs in 18 innings pitched
22 Meteorology For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Solve the equation for a If the atmospheric temperature is -655 ∘F and the ground temperature is 57 ∘F what is the altitude
Module 2 71 Lesson 3
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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arcourt Publishin
g Com
pany bull Im
age C
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Rand
y D
uch
aineA
lamy
HOT Focus on Higher Order Thinking
23 Explain the Error A student was asked to use the formula for the perimeter of a rectangle P = 2ℓ + 2w to solve for ℓ The student came up with an answer P - 2w = 2ℓ What error did the student make Explain Then solve for ℓ
24 Multi-Step The formula c = 5p + 215 relates c the total cost in dollars of hosting a birthday party at a skating rink to p the number of people attending If Alliersquos parents are willing to spend $300 for a party how many people can attend
25 Multi-Step The formula for the area of a triangle is A = 1 __ 2 bh in which b represents the length of thebase and h represents the height If a triangle has an area of 192 mm2 and the height is 12 mm what is the measure of the base
Lesson Performance TaskThe following table shows the average low temperatures in Fahrenheit for the city of Boston for several months during the year The formula F = 9 __ 5 C + 32 allows you to determine the temperature in Fahrenheit when given the temperature in Celsius
MonthTemperature in
FahrenheitTemperature in
Celsius
January 22deg
April 41deg
July 65deg
October 47deg
December 28deg
a Use the information given to determine the average low temperatures in Celsius
b Would it ever be possible for the temperature in Celsius to have a greater value than the temperature in Fahrenheit Explain why or why not
Module 2 72 Lesson 3
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
Name Class Date
Resource Locker
copy H
oug
hton
Mif
flin
Har
cour
t Pub
lishi
ng
Com
pan
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mag
e cr
edit
s copy
Patr
ick
Lan
eSo
mos
Imag
esC
orb
is
Explore Creating Inequalities from Verbal DescriptionsAn inequality is a statement that compares two expressions that are not strictly equal by using one of the following inequality signs
Symbol Meaning
lt is less than
le is less than or equal to
gt is greater than
ge is greater than or equal to
ne is not equal to
You have probably seen a sign at an amusement park saying something like ldquoYou must be at least 48 inches tall to ride this riderdquo This statement could be written as h ge 48 in where h represents the height of a person allowed to ride
Nora is planning a birthday party for her little sister Colleen Norarsquos budget will allow her to spend no more than $50 for party supplies Eight children including Colleen will attend the party and Nora wants to determine how much she could spend on party favors for each child She will also purchase a cake for $10 Write an inequality that represents the situation and find possible solutions
A First let c represent the cost of a party favor for each child Write an expression for the total cost of the party as a function of c
c +
B Which inequality symbol should be used to represent the phrase ldquono more thanrdquo
C Write the inequality that represents Norarsquos budget goal
8c + 10 le
D Suppose Nora finds party favors that cost $4 each Use a value of 4 for c and check to see if this inequality is true
8 middot 4 + 10 le 50
le 50
Module 2 73 Lesson 4
24 Creating and Solving Inequalities
Essential Question How do you write and solve an inequality that represents a real-world situation
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
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pany
Is the inequality true
Could Nora buy $6 party favors for all of her guests without going over budget
Reflect
1 Why does an inequality represent Norarsquos budget calculation better than an equation
2 The solution set of an inequality consists of all values that make the statement true Describe the whole dollar amounts that are in the solution set for this situation
Explain 1 Creating and Solving Inequalities Involving the Distributive Property
You may need to use the Distributive Property before you can solve an inequality
Distributive Property If a b and c are real numbers then a(b + c) = ab + ac
The inequality sign must be reversed when multiplying or dividing both sides of an inequality by a negative number
Example 1
A Trina is buying 12 shirts for the drama club She will choose a style for the blank shirts and then pay an additional charge of $275 for each shirt to have the club logo If Trina cannot spend more than $99 how much can she spend on each blank shirt Write and solve an inequality to find the possible cost of each blank shirt
Let s represent the cost of each blank shirt
Write an inequality to represent the situation 12(s + 275) le 99
Use the Distributive Property 12s + 33 le 99
Subtraction Property of Inequality 12s + 33 - 33 le 99 - 33
Simplify 12s le 66
Division Property of Inequality 12s ___ 12 le 66 __ 12
Simplify s le 55
Module 2 74 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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oug
hton
Mif
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Har
cour
t Pub
lishi
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Com
pan
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Check your answer
Since s le 55 check a smaller number 12(5 + 275) le 99
Trina can order blank shirts that cost $550 or less 93 le 99 true
B Sergio needs to buy gifts for 8 friends He wants to give the same gift to all his friends and he plans to have the gifts wrapped for an additional charge of $150 each If Sergio spends at least $70 he will receive free shipping on his order Write and solve an inequality to determine how much Sergio needs to spend on each gift in order to receive free shipping
Let g be the cost of one gift
Write an inequality to represent the situation ( g + ) ge 70
Use the Distributive Property g + ge 70
Subtraction Property of Inequality g + 12 - ge 70 -
Simplify 8g ge
Division Property of Inequality 8g _
ge 58 _
Simplify g ge
Check your answer
Since g ge 725 check a larger number 8(8 + 150) ge 70
Sergio must spend at least on each gift ge 70
Reflect
3 Discussion Why is the first step in solving the inequality to use the Distributive Property instead of working inside the parentheses
Your Turn
4 Zachary is planning to send a video game to each of his two brothers If he buys the same game for both brothers and pays $475 to ship each game how much can he spend on each game without spending more than $100 Write and solve an inequality for this situation
Solve each inequality
5 4 _ 3 (6x + 9) lt 4 6 -2 ( 1 _ 4 x + 2 ) ge 5
Module 2 75 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany
Explain 2 Creating and Solving Inequalities with Variables on Both Sides
Some inequalities have variable terms on both sides of the inequality symbol You can solve these inequalities the same way you solved equations with variables on both sides Use the properties of inequality to collect all the variable terms on one side and all the constant terms on the other side
Example 2
A The Daily Info charges a fee of $650 plus $80 per week to run an ad The Peoplersquos Paper charges $145 per week For how many weeks must an ad run for the total cost at the Daily Info to be less expensive than the cost at the Peoplersquos Paper Let w be the number of weeks the ad runs in the paper
Write an inequality to represent the situation 650 + 80w lt 145w
Subtraction Property of Inequality 650 + 80w - 80w lt 145w - 80w
Simplify 650 lt 65w
Division Property of Inequality 650 _ 65 lt 65w _ 65
Simplify 10 lt w
The total cost at the Daily Info is less than the cost at the Peoplersquos Paper if the ad runs for more than 10 weeks
B The Home Cleaning Company charges $312 to power-wash the siding of a house plus $12 for each window Power Clean charges $36 per window and the price includes power-washing the siding How many windows must a house have to make the total cost from The Home Cleaning Company less expensive than Power Clean Let w be the number of windows
Write an inequality to represent the situation +12w lt 36w
Subtraction Property of Inequality 312 + 12w - lt 36w -
Simplify 312 lt
Division Property of Inequality 312 _ lt 24w _
Simplify lt w
A house must have more than 13 windows for The Home Cleaning Company to be less expensive than Power Clean
Reflect
7 How would the final inequality change if you divided by ndash24 in the next to last step
Your Turn
8 The school band will sell pizzas to raise money for new uniforms The supplier charges $100 plus $4 per pizza The band members sell the pizzas for $7 each Write and solve an inequality to find how many pizzas the band members will have to sell to make a profit
Module 2 76 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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oug
hton
Mif
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Har
cour
t Pub
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Com
pan
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Elaborate
9 Which inequality symbol would you use to represent the following words or phrases Can you come up with more examples
a at most b farther than c younger than d up to
10 Discussion How are the steps to solving an inequality similar to those for solving an equation How are they different
11 Essential Question Check-In How can you write an inequality that represents a real-world situation
Write an inequality that represents the description and then solve
1 Max has more than 5 carrots (number of carrots Max has = c)
2 Brigitte is shorter than 5 feet (Brigittersquos height = h)
3 Twice a number (x) is less than 10 4 Six more than five times a number (x) is at least twenty-one
5 Dave has $15 to spend on an $8 book and two birthday cards (c) for his friends How much can he spend on each card if he buys the same card for each friend
6 Toni can carry up to 18 lb in her backpack Her lunch weighs 1 lb her gym clothes weigh 2 lb and her books (b) weigh 3 lb each How many books can she carry in her backpack
Evaluate Homework and Practice
bull Online Homeworkbull Hints and Helpbull Extra Practice
Module 2 77 Lesson 4
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Solve each inequality
7 3 (x - 2) gt -3 8 5 + 5 (x + 4) le 20 9 3 + 1 _ 2 (3 - x) lt -7
10 3 (x + 6) - 2 (x + 2) ge 10 11 5 (3 - x) -4 (2 - 3x) gt 2 12 1 _ 2 (4x - 2) - 2 _ 3 (6x + 9) le 4
13 x + 1 gt -5 (7 - 2x) 14 5 _ 3 (6x + 3) le 2x - 7
15 2x le - 2 __ 3 (4x + 4) 16 1 __ 2 (-2x - 10) gt 3 (4 - 6x)
17 -5 - 3x ge 2 (10 + 2x) + 3 18 -3 (9x + 20) ge 15x - 20
19 8 ( 1 _ 4 x - 3) + 24 lt 4 ( x + 5 ) 20 6x - 2 (x + 2) gt 2 - 3 (x + 3)
Module 2 78 Lesson 4
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21 Physics A crane cable can support a maximum load of 15000 kg If a bucket has a mass of 2000 kg and gravel has a mass of 1500 kg for every cubic meter how many cubic meters of gravel (g) can be safely lifted by the crane
22 Find the solution set of each inequality below and then determine which inequalities have the same solution set as 1 _ 3 ( -5x - 3 ) lt 14
a 1 _ 3 (5x + 3) gt -14 b 2 _ 5 (10x + 20) gt 44
c - 2 _ 5 (10x + 20) lt -44 d - 1 _ 3 (5x + 3) lt 14
e 2 _ 5 (10x - 20) gt -44 f 1 _ 3 (5x + 3) lt -14
HOT Focus on Higher Order Thinking
23 Explain the Error Sven is trying to find the maximum amount of time he can spend practicing the five scales of piano music he is supposed to be working on He has 60 minutes to practice piano and would like to spend at least 35 minutes playing songs instead of practicing scales So Sven sets up the following inequality where t is the number of minutes he spends on each scale and solves it
60 - 5t le 35-5t le -25
t ge 5
Sven has concluded that he should spend 5 minutes or more on each scale Is this correct If not what mistake did he make Then solve for the correct answer
Module 2 79 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
24 Critical Thinking Anika wants to determine the maximum number of tulip bulbs (t) she can purchase if each bulb costs $150 She will also need to purchase separate pots for each bulb at $125 each and a bag of potting soil for $1000 Set up an inequality to determine how many tulip bulbs Anika can purchase without spending more than $2000 and solve it Can Anika buy exactly enough bulbs and pots to spend the full $2000 Explain Can you think of a better inequality to describe the answer
25 Geometry The area of the triangle shown is no more than 10 square inches
a Write an inequality that can be used to find x
b Solve the inequality from part a c What is the maximum height of the triangle
Lesson Performance TaskWhen planning an airplane route the trip planner must be careful to consider the range the aircraft can travel and the availability of airports to stop and refuel
A large commercial jet airplane burns approximately 5 gallons of fuel per mile flown plus about 8500 gallons of fuel per trip to reach cruising altitude With a useable fuel capacity of 50000 gallons (there is additional fuel reserved for emergencies) describe the acceptable distance for which an airline could establish a non-stop flight
For flights originating from Chicago determine which cities could be safely reached by a non-stop flight
City Distance from Chicago (miles)
Bangalore India 8530
Jakarta Indonesia 9810
Johannesburg South Africa 8680
Moscow Russia 4970
Paris France 4130
Perth Australia 10970
Tokyo Japan 6300
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eva O
lesiaShutterstock
(2x - 3) in
4 in
Module 2 80 Lesson 4
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Name Class Date
Resource Locker
Explore Truth Tables and Compound StatementsA compound statement is formed by combining two or more simple statements A compound statement can be true or false A compound statement involving AND is true when both simple statements are true A compound statement involving OR is true when either one simple statement or both are true
A Complete the truth table
P QP
True or FalseQ
True or FalseP AND Q
True or False
A dog is a mammal Red is a color
A dog is a mammal Red is not a color
A dog is a fish Red is a color
A dog is a fish Red is not a color
B P AND Q is true when
C Complete the truth table
P QP
True or FalseQ
True or FalseP OR Q
True or False
1 is an odd number 2 is an even number
1 is an odd number 2 is an odd number
1 is an even number 2 is an even number
1 is an even number 2 is an odd number
D P OR Q is true when
Reflect
1 Give two simple statements P and Q for which P AND Q is false and P OR Q is true
Module 2 81 Lesson 5
25 Creating and Solving Compound Inequalities
Essential Question How can you solve a compound inequality and graph the solution set
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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Explain 1 Solving Compound Inequalities Involving ANDCombining two or more simple inequalities forms a compound inequality The graph of a compound inequality involving AND is the intersection or the overlapping region of the simple inequality graphs
Compound Inequalities AND
Words Algebra Graph
All real numbers greater than 2AND less than 6
x gt 2 AND x lt 62 lt x lt 6
All real numbers greater than or equal to 2 AND less than or equal to 6
x ge 2 AND x le 62 le x le 6
Example 1 Solve each compound inequality and graph the solutions
A 4 le x + 2 le 8
4 le x + 2 AND x + 2 le 8 Write the compound inequality using AND
4 - 2 le x + 2 - 2 x + 2 - 2 le 8 - 2 Subtract 2 from both sides of each simple inequality
2 le x x le 6 Simplify
Graph 2 le x
Graph x le 6
Graph the intersection by finding where the two graphs overlap
B -5 le 2x + 3 lt 9
-5 - le 2x + 3 - lt 9 - Subtract from each part of the inequality
le 2x lt Simplify
-8 _ le 2x _ lt 6 _ Divide each part of the inequality by
le x lt Simplify
Graph -4 le x
Graph x lt 3
Graph the intersection by finding where the two graphs overlap -1 0 1 2 3 4 5-5-4 -3 -2
0 2 4 6 8 10 12-8-6-4 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 82 Lesson 5
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Reflect
2 Discussion Explain why 2 le x le 6 can be considered the short method for writing the AND compound inequality x ge 2 AND x le 6
YourTurn
Solve each compound inequality and graph the solutions
3 -2 lt x - 3 lt 5
4 -10 lt 3x + 2 le 8
Explain 2 Solving Compound Inequalities Involving ORThe graph of a compound inequality involving OR is the union or the combined region of the simple inequality graphs
Compound Inequalities OR
Words Algebra Graph
All real numbers less than 2OR greater than 6
x lt 2 OR x gt 6
All real numbers less than or equal to 2OR greater than or equal to 6
x le 2 OR x ge 6
-1 0 1 2 3 4 5-5-4 -3 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 83 Lesson 5
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Example 2 Solve each compound inequality and graph the solutions
A -4 + x gt 1 OR -4 + x lt -3
-4 + x gt 1 OR -4 + x lt -3 Write the compound inequality using OR
-4 + 4 + x gt 1 + 4 -4 + 4 + x lt -3 + 4 Add 4 to both sides of each simple inequality
x gt 5 x lt 1 Simplify
Graph x gt 5
Graph x lt 1
Graph the union by combining the graphs
B 2x le 6 OR 3x gt 12
2x le 6 OR 3x gt 12 Write the compound inequality using OR
2x _ le 6 _ OR 3x _ gt 12 _ Divide the first simple inequality by
x le OR x gt
Graph x le 3
Graph x gt 4
Graph the union by combining the graphs
Reflect
5 Critical Thinking What kind of compound inequality has no solution
Divide the second simple inequality by
Simplify
0 1 2 3 4 5 6-4 -3 -2 -1
-0 1 2 3 4 5 6-4 -3 -2 -1
Module 2 84 Lesson 5
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Your Turn
Solve each compound inequality and graph the solutions
6 x - 5 ge -2 OR x -5 le -6
7 4x -1 lt 15 OR 8x ge 48
Explain 3 Creating Compound Inequalities From GraphsGiven a number line graph with a solution set graphed you can create a compound inequality to fit the graph
Example 3 Write the compound inequality shown by each graph
A
The shaded portion of the graph is not between two values so the compound inequality involves OR
On the left the graph shows an arrow pointing left from -1 and a solid circle so use le
The inequality is x le -1
On the right the graph shows an arrow pointing right from 7 and a solid circle so use ge
The inequality is x ge 7
The compound inequality is x le -1 OR x ge 7
B
The graph is shaded between the values and so the compound inequality involves AND
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The compound inequality is
-1 0 1 2 3 4 5-5-4 -3 -2
4 5 6 7 8 9 100 1 2 3
2 3 4 5 6 7 8-2 -1 0 1
10 2 3 4 5 6 7 8 9-1
Module 2 85 Lesson 5
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oug
hton Mifflin H
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Reflect
8 What is a short method to write the compound inequality x ge 0 AND x lt 6
Your Turn
Write the compound inequality shown by each graph
9
10
Explain 4 Expressing Acceptable Levels with Compound Inequalities
You can express quality-controls levels in real-world problems using compound inequalities
Example 4 Write a compound inequality to represent the indicated quality-control level and graph the solutions
A The recommended pH level for swimming pool water is between 72 and 76 inclusive
Let p be the pH level of swimming pool water
72 is less than or equal to pH level is less than or equal to 76
72 le p le 76
The compound inequality is 72 le p le 76
Graph the solutions
0-10 -8-9 -7-6 -5-4 -3 -2 -1
71 72 73 74 75 76 77 78 79 8070
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 86 Lesson 5
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oug
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B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
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oug
hton Mifflin H
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pany
bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
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oug
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Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
arcourt Publishin
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pany bull Im
age C
redits copy
Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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Mif
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cour
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Com
pan
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copy
bik
erid
erlo
nd
onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
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pan
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Solve
2 (x + 4) = 4 2 (x - 2) - 2x
2 (x + 4) = (x - 2) - 2x Simplify
2x + = 8x - - 2x Distributive Property
2x + 8 = x - 16
2x + 8 + = 6x - 16 + Addition Property of Equality
2x + = 6x
2x + 24 - x = 6x - x Subtraction Property of Equality
24 = x
24 _ = x _ Division Property of Equality
= x
Jill works hours per day Kim works hours per day and Jack works
hours per day
Justify and Evaluate
Substitute x = 6 into the original equation
2 (6 + 4) = 4 2 (6 - 2) - 2x
2 ( ) = 8 ( ) - 2 ( ) =
Your Turn
Write and solve an equation to solve the problem
9 Lisa is 10 centimeters taller than her friend Ian Ian is 14 centimeters taller than Jim Every month their heights increase by 2 centimeters In 7 months the sum of Ianrsquos and Jimrsquos heights will be 170 centimeters more than Lisarsquos height How tall is Ian now
Height now Height after 7 months
Module 2 61 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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oug
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pany
Elaborate
10 How can you use properties to solve equations with variables on both sides
11 How is a table helpful when constructing equations
12 When solving a real-world problem to find a personrsquos age would a negative solution make sense Explain
13 Essential Question Check-In How do you write an equation to represent a real-world situation
bull Online Homeworkbull Hints and Helpbull Extra Practice
Write an equation for each description
1 The sum of 14 and a number is equal to 17 2 A number increased by 10 is 114
3 The difference between a number and 12 is 20 4 Ten times the sum of half a number and 6 is 8
5 Two-thirds a number plus 4 is 7 6 Tanmayi wants to raise $175 for a school fundraiser She has raised $120 so far How much more does she need to reach her goal
7 Hector is visiting a cousin who lives 350 miles away He has driven 90 miles How many more miles does he need to drive to reach his cousinrsquos home
8 The length of a rectangle is twice its width The perimeter of the rectangle is 126 feet
Evaluate Homework and Practice
Module 2 62 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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(t)copy
Pete
r K
imS
hutt
erst
ock
Write and solve an equation for each situation
9 In one baseball season Peter hit twice the difference of the number of home runs Alice hit and 6 Altogether they hit 18 home runs How many home runs did each player hit that season
10 The perimeter of a parallelogram is 72 meters The width of the parallelogram is 4 meters less than its length Find the length and the width of the parallelogram
11 One month Ruby worked 6 hours more than Isaac and Svetlana worked 4 times as many hours as Ruby Together they worked 126 hours Find the number of hours each person worked
12 In one day Annie traveled 5 times the sum of the number of hours Brian traveled and 2 Together they traveled 20 hours Find the number of hours each person traveled
13 Xian and his cousin Kai both collect stamps Xian has 56 stamps and Kai has 80 stamps The boys recently joined different stamp-collecting clubs Xianrsquos club will send him 12 new stamps per month Kairsquos club will send him 8 new stamps per month After how many months will Xian and Kai have the same number of stamps How many stamps will each have
14 Kenya plans to make a down payment plus monthly payments in order to buy a motorcycle At one dealer she would pay $2500 down and $150 each month At another dealer she would pay $3000 down and $125 each month After how many months would the total amount paid be the same for both dealers What would that amount be
ℓ meters
(ℓ - 4) meters
Module 2 63 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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15 Community Gym charges a $50 membership fee and a $55 monthly fee Workout Gym charges a $200 membership fee and a $45 monthly fee After how many months will the total amount of money paid to both gyms be the same What will the amount be
16 Tina is saving to buy a notebook computer She has two options The first option is to put $200 away initially and save $10 every month The second option is to put $100 away initially and save $30 every month After how many months would Tina save the same amount using either option How much would she save with either option
Use the table to answer each question
Starting Salary Yearly Salary Increase
Company A $24000 $3000
Company B $30000 $2400
Company C $36000 $2000
17 After how many years are the salaries offered by Company A and Company B the same
18 After how many years are the salaries offered by Company B and Company C the same
19 Paul started work at Company B ten years ago at the salary shown in the table At the same time Sharla started at Company C at the salary shown in the table Who earned more during the last year How much more
20 Georgersquos page contains twice as many typed words as Billrsquos page and Billrsquos page contains 50 fewer words than Charliersquos page If each person can type 60 words per minute after one minute the difference between twice the number of words on Billrsquos page and the number of words on Charliersquos page is 210 How many words did Billrsquos page contain initially Use a table to organize the information
Initial number of words
Total number of words after one minute
Module 2 64 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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Mif
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pan
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21 Geometry Sammie bought just enough fencing to border either a rectangular plot or a square plot as shown The perimeters of the plots are the same How many meters of fencing did she buy
HOT Focus on Higher Order Thinking
22 Justify Reasoning Suppose you want to solve the equation 2a + b = 2a where a and b are nonzero real numbers Describe the solution to this equation Justify your description
23 Multi-step A patio in the shape of a rectangle is fenced on all sides with 134 feet of fencing The patio is 5 feet less wide than it is long
a What information can be used to solve the problem How can you find the information
b Describe how to find the area of the patio What is the area of the patio
24 Explain the Error Kevin and Brittany write an equation to represent the following relationship and both students solve their equation Who found the correct equation and solution Why is the other person incorrect
5 times the difference of a number and 20 is the same as half the sum of 4 more than 4 times a number
Kevin Brittany
5 (x - 20) = 1 _ 2 (4x + 4) 5 (20 + x) = 1 _ 2 (4x + 4)
5x - 100 = 2x + 2 100 - 5x = 2x + 2
3x - 100 = 2 100 - 7x = 2
3x = 102 -7x = -98
x = 34 x = 14
(3x + 2) meters
(x + 2) meters
(x + 2) meters
(x - 1) meters
ℓ feet
(ℓ - 5) feet
Module 2 65 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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25 What If Alexa and Zack are solving the following problem
The number of miles on Car A is 50 miles more than the number of miles on Car B and the number of miles on Car B is 30 miles more than the number of miles on Car C All the cars travel 50 miles in 1 hour After 1 hour twice the number of miles on Car A is 70 miles less than 3 times the number of miles on Car C How many miles were there on Car B initially
Alexa assumes there are m miles on Car B Zack assumes there are m miles on Car C Will Zackrsquos answer be the same as Alexarsquos answer Explain
Lesson Performance Task
Stacy Oliver and Jivesh each plan to put a certain amount of money into their savings accounts that earn simple interest of 6 per year Stacy puts $550 more than Jivesh and Oliver puts in 2 times as much as Jivesh After a year the amount in Stacyrsquos account is 2 times the sum of $212 and the amount in Oliverrsquos account How much does each person initially put into his or her account Who had the most money in his or her account after a year Who had the least Explain
Zackrsquos Table Initial Miles
Miles after One Hour
Alexarsquos Table Initial Miles
Miles after One Hour
Amount in Account Initially Amount in Account after One Year
Module 2 66 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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Name Class Date
Resource Locker
Explore Rearranging Mathematical FormulasLiteral Equations are equations that contain two or more variables There are many literal equations in the form of math science and engineering formulas These formulas may seem like they can only be solved for the variable that is isolated on one side of the formula By using inverse operations and the properties of equality a formula can be rearranged so any variable in the formula can be isolated It is no different than how equations are solved by using inverse operations and the properties of equality
How can you solve the equation 42 = 6x
A42 _ = 6x _ What is the reason for dividing
Why divide by
= x By rearranging the equation x was isolated and the solution was found
The mathematical formula for the volume of a rectangular prism B = Vh or V = ℓwh is a literal equation V represents volume ℓ represents length w represents width and h represents height Using inverse operations the formula can be rearranged to solve for any one of the variables that might be unknown Like solving for x a formula can be rearranged to isolate a variable
B In the formula V = ℓwh the variable h needs to be isolated
The operation of is used in the formula The inverse
operation should be used
to isolate
C V _____ = ℓwh _____
V _ =
The formula rearranged in this way can easily produce the height of the rectangular prism when the volume length and width are known
Reflect
1 Using the formula for a rectangular prism rewrite the formula to solve for ℓ
ℓw
h
Module 2 67 Lesson 3
23 Solving for a VariableEssential Question How do you rewrite formulas and literal equations
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otosCorb
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Explain 1 Rearranging Scientific FormulasUse inverse operations to isolate the unknown variable in a scientific formula
The formula for density is D = m __ V Lead has a very high density of 11340 kg m 3 Plastic foam has a very low density of 75 kg m 3 The formula for density can be rearranged to solve for V volume or m mass
Example 1
A A sinker on a fishing line is made of lead and has a volume of 0000015 m 3 What is the mass of the sinker
The density formula can be rearranged to isolate m the mass The values for volume and density can then be substituted into the formula to find the mass
D = m _ V
DV = ( m _ V ) V DV = m
(11340 kg m 3 ) (0000015 m 3 ) = m
017 kg asymp m
B The design for a life preserver requires 03 kilogram of plastic foam to provide proper buoyancy What is the volume of the plastic foam required
Rearrange the density formula to isolate V
D = m _ V
(D) V = m _ V
DV =
DV _ = m _
V =
Now substitute the given values
V = _
V = m 3
Your Turn
2 For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Determine the altitude in feet when t is -275 ∘F and g is 60 ∘F
Module 2 68 Lesson 3
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Explain 2 Rearranging Literal EquationsUsing inverse operations to rearrange literal equations can be applied to any formula The interest formula I = prt is another example of a literal equation In the formula I represents interest p the principal or the initial amount to which interest will be applied r the rate at which interest will be paid and t is the time in years
Example 2
A Find the number of years used in the calculation of a $1000 loan at an interest rate of 5 with interest totaling $600
Solve the formula for t
I = prt
I _ pr = prt
_ pr
I _ pr = t
Substitute the given values Since the interest rate is 5 r = 005$600 __
$1000 middot 005 = t
12 = t
So the length of time for the loan is 12 years
B Determine the interest rate for a $2000 loan that will be paid off in 4 years with interest totaling $640 In order to find the interest rate solve the formula for r
I = prt
I _ = prt _
_ = r
Now substitute the values and simplify
__
( ) ( ) = r
008 = r
So the interest rate is per year
Your Turn
3 The formula y = mx + b is the slope-intercept form of the equation of a line Solve the equation for m
Module 2 69 Lesson 3
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bull Online Homeworkbull Hints and Helpbull Extra Practice
Solve for the indicated variable in each mathematical formula
1 C = 2πr for r 2 A = 1 __ 2 bh for b 3 y = mx + b for x
4 A = 1 __ 2 (a + b)h for h 5 V = πr2h for h 6 SA = 2πr2 + 2πrh for h
Solve for the indicated variable in each scientific formula
7 d = rt for t 8 PV = nRT for T
9 A = FV - OV _______ T for OV 10 C = Wtc _ 1000 for W
Evaluate Homework and Practice
Elaborate
4 Discussion What could be a reason for isolating a variable in a literal equation
5 Describe a situation in which a formula could be used more easily if it were rearranged Include the formula in your description
6 Essential Question Check-In How do you isolate a variable
Module 2 70 Lesson 3
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cean
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orb
is
Solve for the indicated variable in each literal equation
11 2p + 5r = q for p 12 -10 = xy + z for x 13 a __ b = c for b
14 h - 4 _ j = k for j 15 x __ 5 - g = a for x 16 5p + 9c = p for c
17 2 __ 5 (z + 1) = y for z 18 g (h + 2 __ 3 ) = 1 for h 19 a(n - 3) + 8 = bn for n
20 Which is a possible way to rewrite the equation y = 3x + 3b to solve for b
A b = y - 3x
_ 3 C b = y - 3
_____ 3x
B b = 3(y - 3x) D b = x(y - 3)
21 Sports To find a baseball pitcherrsquos earned run average (ERA) you can use the formula Ei = 9r in which E represents ERA i represents the number of innings pitched and r represents the number of earned runs allowed Solve the equation for E What is a pitcherrsquos ERA if he allows 5 earned runs in 18 innings pitched
22 Meteorology For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Solve the equation for a If the atmospheric temperature is -655 ∘F and the ground temperature is 57 ∘F what is the altitude
Module 2 71 Lesson 3
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Rand
y D
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aineA
lamy
HOT Focus on Higher Order Thinking
23 Explain the Error A student was asked to use the formula for the perimeter of a rectangle P = 2ℓ + 2w to solve for ℓ The student came up with an answer P - 2w = 2ℓ What error did the student make Explain Then solve for ℓ
24 Multi-Step The formula c = 5p + 215 relates c the total cost in dollars of hosting a birthday party at a skating rink to p the number of people attending If Alliersquos parents are willing to spend $300 for a party how many people can attend
25 Multi-Step The formula for the area of a triangle is A = 1 __ 2 bh in which b represents the length of thebase and h represents the height If a triangle has an area of 192 mm2 and the height is 12 mm what is the measure of the base
Lesson Performance TaskThe following table shows the average low temperatures in Fahrenheit for the city of Boston for several months during the year The formula F = 9 __ 5 C + 32 allows you to determine the temperature in Fahrenheit when given the temperature in Celsius
MonthTemperature in
FahrenheitTemperature in
Celsius
January 22deg
April 41deg
July 65deg
October 47deg
December 28deg
a Use the information given to determine the average low temperatures in Celsius
b Would it ever be possible for the temperature in Celsius to have a greater value than the temperature in Fahrenheit Explain why or why not
Module 2 72 Lesson 3
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
Name Class Date
Resource Locker
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edit
s copy
Patr
ick
Lan
eSo
mos
Imag
esC
orb
is
Explore Creating Inequalities from Verbal DescriptionsAn inequality is a statement that compares two expressions that are not strictly equal by using one of the following inequality signs
Symbol Meaning
lt is less than
le is less than or equal to
gt is greater than
ge is greater than or equal to
ne is not equal to
You have probably seen a sign at an amusement park saying something like ldquoYou must be at least 48 inches tall to ride this riderdquo This statement could be written as h ge 48 in where h represents the height of a person allowed to ride
Nora is planning a birthday party for her little sister Colleen Norarsquos budget will allow her to spend no more than $50 for party supplies Eight children including Colleen will attend the party and Nora wants to determine how much she could spend on party favors for each child She will also purchase a cake for $10 Write an inequality that represents the situation and find possible solutions
A First let c represent the cost of a party favor for each child Write an expression for the total cost of the party as a function of c
c +
B Which inequality symbol should be used to represent the phrase ldquono more thanrdquo
C Write the inequality that represents Norarsquos budget goal
8c + 10 le
D Suppose Nora finds party favors that cost $4 each Use a value of 4 for c and check to see if this inequality is true
8 middot 4 + 10 le 50
le 50
Module 2 73 Lesson 4
24 Creating and Solving Inequalities
Essential Question How do you write and solve an inequality that represents a real-world situation
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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Is the inequality true
Could Nora buy $6 party favors for all of her guests without going over budget
Reflect
1 Why does an inequality represent Norarsquos budget calculation better than an equation
2 The solution set of an inequality consists of all values that make the statement true Describe the whole dollar amounts that are in the solution set for this situation
Explain 1 Creating and Solving Inequalities Involving the Distributive Property
You may need to use the Distributive Property before you can solve an inequality
Distributive Property If a b and c are real numbers then a(b + c) = ab + ac
The inequality sign must be reversed when multiplying or dividing both sides of an inequality by a negative number
Example 1
A Trina is buying 12 shirts for the drama club She will choose a style for the blank shirts and then pay an additional charge of $275 for each shirt to have the club logo If Trina cannot spend more than $99 how much can she spend on each blank shirt Write and solve an inequality to find the possible cost of each blank shirt
Let s represent the cost of each blank shirt
Write an inequality to represent the situation 12(s + 275) le 99
Use the Distributive Property 12s + 33 le 99
Subtraction Property of Inequality 12s + 33 - 33 le 99 - 33
Simplify 12s le 66
Division Property of Inequality 12s ___ 12 le 66 __ 12
Simplify s le 55
Module 2 74 Lesson 4
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Check your answer
Since s le 55 check a smaller number 12(5 + 275) le 99
Trina can order blank shirts that cost $550 or less 93 le 99 true
B Sergio needs to buy gifts for 8 friends He wants to give the same gift to all his friends and he plans to have the gifts wrapped for an additional charge of $150 each If Sergio spends at least $70 he will receive free shipping on his order Write and solve an inequality to determine how much Sergio needs to spend on each gift in order to receive free shipping
Let g be the cost of one gift
Write an inequality to represent the situation ( g + ) ge 70
Use the Distributive Property g + ge 70
Subtraction Property of Inequality g + 12 - ge 70 -
Simplify 8g ge
Division Property of Inequality 8g _
ge 58 _
Simplify g ge
Check your answer
Since g ge 725 check a larger number 8(8 + 150) ge 70
Sergio must spend at least on each gift ge 70
Reflect
3 Discussion Why is the first step in solving the inequality to use the Distributive Property instead of working inside the parentheses
Your Turn
4 Zachary is planning to send a video game to each of his two brothers If he buys the same game for both brothers and pays $475 to ship each game how much can he spend on each game without spending more than $100 Write and solve an inequality for this situation
Solve each inequality
5 4 _ 3 (6x + 9) lt 4 6 -2 ( 1 _ 4 x + 2 ) ge 5
Module 2 75 Lesson 4
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Explain 2 Creating and Solving Inequalities with Variables on Both Sides
Some inequalities have variable terms on both sides of the inequality symbol You can solve these inequalities the same way you solved equations with variables on both sides Use the properties of inequality to collect all the variable terms on one side and all the constant terms on the other side
Example 2
A The Daily Info charges a fee of $650 plus $80 per week to run an ad The Peoplersquos Paper charges $145 per week For how many weeks must an ad run for the total cost at the Daily Info to be less expensive than the cost at the Peoplersquos Paper Let w be the number of weeks the ad runs in the paper
Write an inequality to represent the situation 650 + 80w lt 145w
Subtraction Property of Inequality 650 + 80w - 80w lt 145w - 80w
Simplify 650 lt 65w
Division Property of Inequality 650 _ 65 lt 65w _ 65
Simplify 10 lt w
The total cost at the Daily Info is less than the cost at the Peoplersquos Paper if the ad runs for more than 10 weeks
B The Home Cleaning Company charges $312 to power-wash the siding of a house plus $12 for each window Power Clean charges $36 per window and the price includes power-washing the siding How many windows must a house have to make the total cost from The Home Cleaning Company less expensive than Power Clean Let w be the number of windows
Write an inequality to represent the situation +12w lt 36w
Subtraction Property of Inequality 312 + 12w - lt 36w -
Simplify 312 lt
Division Property of Inequality 312 _ lt 24w _
Simplify lt w
A house must have more than 13 windows for The Home Cleaning Company to be less expensive than Power Clean
Reflect
7 How would the final inequality change if you divided by ndash24 in the next to last step
Your Turn
8 The school band will sell pizzas to raise money for new uniforms The supplier charges $100 plus $4 per pizza The band members sell the pizzas for $7 each Write and solve an inequality to find how many pizzas the band members will have to sell to make a profit
Module 2 76 Lesson 4
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Elaborate
9 Which inequality symbol would you use to represent the following words or phrases Can you come up with more examples
a at most b farther than c younger than d up to
10 Discussion How are the steps to solving an inequality similar to those for solving an equation How are they different
11 Essential Question Check-In How can you write an inequality that represents a real-world situation
Write an inequality that represents the description and then solve
1 Max has more than 5 carrots (number of carrots Max has = c)
2 Brigitte is shorter than 5 feet (Brigittersquos height = h)
3 Twice a number (x) is less than 10 4 Six more than five times a number (x) is at least twenty-one
5 Dave has $15 to spend on an $8 book and two birthday cards (c) for his friends How much can he spend on each card if he buys the same card for each friend
6 Toni can carry up to 18 lb in her backpack Her lunch weighs 1 lb her gym clothes weigh 2 lb and her books (b) weigh 3 lb each How many books can she carry in her backpack
Evaluate Homework and Practice
bull Online Homeworkbull Hints and Helpbull Extra Practice
Module 2 77 Lesson 4
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Solve each inequality
7 3 (x - 2) gt -3 8 5 + 5 (x + 4) le 20 9 3 + 1 _ 2 (3 - x) lt -7
10 3 (x + 6) - 2 (x + 2) ge 10 11 5 (3 - x) -4 (2 - 3x) gt 2 12 1 _ 2 (4x - 2) - 2 _ 3 (6x + 9) le 4
13 x + 1 gt -5 (7 - 2x) 14 5 _ 3 (6x + 3) le 2x - 7
15 2x le - 2 __ 3 (4x + 4) 16 1 __ 2 (-2x - 10) gt 3 (4 - 6x)
17 -5 - 3x ge 2 (10 + 2x) + 3 18 -3 (9x + 20) ge 15x - 20
19 8 ( 1 _ 4 x - 3) + 24 lt 4 ( x + 5 ) 20 6x - 2 (x + 2) gt 2 - 3 (x + 3)
Module 2 78 Lesson 4
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21 Physics A crane cable can support a maximum load of 15000 kg If a bucket has a mass of 2000 kg and gravel has a mass of 1500 kg for every cubic meter how many cubic meters of gravel (g) can be safely lifted by the crane
22 Find the solution set of each inequality below and then determine which inequalities have the same solution set as 1 _ 3 ( -5x - 3 ) lt 14
a 1 _ 3 (5x + 3) gt -14 b 2 _ 5 (10x + 20) gt 44
c - 2 _ 5 (10x + 20) lt -44 d - 1 _ 3 (5x + 3) lt 14
e 2 _ 5 (10x - 20) gt -44 f 1 _ 3 (5x + 3) lt -14
HOT Focus on Higher Order Thinking
23 Explain the Error Sven is trying to find the maximum amount of time he can spend practicing the five scales of piano music he is supposed to be working on He has 60 minutes to practice piano and would like to spend at least 35 minutes playing songs instead of practicing scales So Sven sets up the following inequality where t is the number of minutes he spends on each scale and solves it
60 - 5t le 35-5t le -25
t ge 5
Sven has concluded that he should spend 5 minutes or more on each scale Is this correct If not what mistake did he make Then solve for the correct answer
Module 2 79 Lesson 4
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24 Critical Thinking Anika wants to determine the maximum number of tulip bulbs (t) she can purchase if each bulb costs $150 She will also need to purchase separate pots for each bulb at $125 each and a bag of potting soil for $1000 Set up an inequality to determine how many tulip bulbs Anika can purchase without spending more than $2000 and solve it Can Anika buy exactly enough bulbs and pots to spend the full $2000 Explain Can you think of a better inequality to describe the answer
25 Geometry The area of the triangle shown is no more than 10 square inches
a Write an inequality that can be used to find x
b Solve the inequality from part a c What is the maximum height of the triangle
Lesson Performance TaskWhen planning an airplane route the trip planner must be careful to consider the range the aircraft can travel and the availability of airports to stop and refuel
A large commercial jet airplane burns approximately 5 gallons of fuel per mile flown plus about 8500 gallons of fuel per trip to reach cruising altitude With a useable fuel capacity of 50000 gallons (there is additional fuel reserved for emergencies) describe the acceptable distance for which an airline could establish a non-stop flight
For flights originating from Chicago determine which cities could be safely reached by a non-stop flight
City Distance from Chicago (miles)
Bangalore India 8530
Jakarta Indonesia 9810
Johannesburg South Africa 8680
Moscow Russia 4970
Paris France 4130
Perth Australia 10970
Tokyo Japan 6300
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eva O
lesiaShutterstock
(2x - 3) in
4 in
Module 2 80 Lesson 4
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Name Class Date
Resource Locker
Explore Truth Tables and Compound StatementsA compound statement is formed by combining two or more simple statements A compound statement can be true or false A compound statement involving AND is true when both simple statements are true A compound statement involving OR is true when either one simple statement or both are true
A Complete the truth table
P QP
True or FalseQ
True or FalseP AND Q
True or False
A dog is a mammal Red is a color
A dog is a mammal Red is not a color
A dog is a fish Red is a color
A dog is a fish Red is not a color
B P AND Q is true when
C Complete the truth table
P QP
True or FalseQ
True or FalseP OR Q
True or False
1 is an odd number 2 is an even number
1 is an odd number 2 is an odd number
1 is an even number 2 is an even number
1 is an even number 2 is an odd number
D P OR Q is true when
Reflect
1 Give two simple statements P and Q for which P AND Q is false and P OR Q is true
Module 2 81 Lesson 5
25 Creating and Solving Compound Inequalities
Essential Question How can you solve a compound inequality and graph the solution set
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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Explain 1 Solving Compound Inequalities Involving ANDCombining two or more simple inequalities forms a compound inequality The graph of a compound inequality involving AND is the intersection or the overlapping region of the simple inequality graphs
Compound Inequalities AND
Words Algebra Graph
All real numbers greater than 2AND less than 6
x gt 2 AND x lt 62 lt x lt 6
All real numbers greater than or equal to 2 AND less than or equal to 6
x ge 2 AND x le 62 le x le 6
Example 1 Solve each compound inequality and graph the solutions
A 4 le x + 2 le 8
4 le x + 2 AND x + 2 le 8 Write the compound inequality using AND
4 - 2 le x + 2 - 2 x + 2 - 2 le 8 - 2 Subtract 2 from both sides of each simple inequality
2 le x x le 6 Simplify
Graph 2 le x
Graph x le 6
Graph the intersection by finding where the two graphs overlap
B -5 le 2x + 3 lt 9
-5 - le 2x + 3 - lt 9 - Subtract from each part of the inequality
le 2x lt Simplify
-8 _ le 2x _ lt 6 _ Divide each part of the inequality by
le x lt Simplify
Graph -4 le x
Graph x lt 3
Graph the intersection by finding where the two graphs overlap -1 0 1 2 3 4 5-5-4 -3 -2
0 2 4 6 8 10 12-8-6-4 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 82 Lesson 5
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Reflect
2 Discussion Explain why 2 le x le 6 can be considered the short method for writing the AND compound inequality x ge 2 AND x le 6
YourTurn
Solve each compound inequality and graph the solutions
3 -2 lt x - 3 lt 5
4 -10 lt 3x + 2 le 8
Explain 2 Solving Compound Inequalities Involving ORThe graph of a compound inequality involving OR is the union or the combined region of the simple inequality graphs
Compound Inequalities OR
Words Algebra Graph
All real numbers less than 2OR greater than 6
x lt 2 OR x gt 6
All real numbers less than or equal to 2OR greater than or equal to 6
x le 2 OR x ge 6
-1 0 1 2 3 4 5-5-4 -3 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 83 Lesson 5
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Example 2 Solve each compound inequality and graph the solutions
A -4 + x gt 1 OR -4 + x lt -3
-4 + x gt 1 OR -4 + x lt -3 Write the compound inequality using OR
-4 + 4 + x gt 1 + 4 -4 + 4 + x lt -3 + 4 Add 4 to both sides of each simple inequality
x gt 5 x lt 1 Simplify
Graph x gt 5
Graph x lt 1
Graph the union by combining the graphs
B 2x le 6 OR 3x gt 12
2x le 6 OR 3x gt 12 Write the compound inequality using OR
2x _ le 6 _ OR 3x _ gt 12 _ Divide the first simple inequality by
x le OR x gt
Graph x le 3
Graph x gt 4
Graph the union by combining the graphs
Reflect
5 Critical Thinking What kind of compound inequality has no solution
Divide the second simple inequality by
Simplify
0 1 2 3 4 5 6-4 -3 -2 -1
-0 1 2 3 4 5 6-4 -3 -2 -1
Module 2 84 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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pan
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Your Turn
Solve each compound inequality and graph the solutions
6 x - 5 ge -2 OR x -5 le -6
7 4x -1 lt 15 OR 8x ge 48
Explain 3 Creating Compound Inequalities From GraphsGiven a number line graph with a solution set graphed you can create a compound inequality to fit the graph
Example 3 Write the compound inequality shown by each graph
A
The shaded portion of the graph is not between two values so the compound inequality involves OR
On the left the graph shows an arrow pointing left from -1 and a solid circle so use le
The inequality is x le -1
On the right the graph shows an arrow pointing right from 7 and a solid circle so use ge
The inequality is x ge 7
The compound inequality is x le -1 OR x ge 7
B
The graph is shaded between the values and so the compound inequality involves AND
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The compound inequality is
-1 0 1 2 3 4 5-5-4 -3 -2
4 5 6 7 8 9 100 1 2 3
2 3 4 5 6 7 8-2 -1 0 1
10 2 3 4 5 6 7 8 9-1
Module 2 85 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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Reflect
8 What is a short method to write the compound inequality x ge 0 AND x lt 6
Your Turn
Write the compound inequality shown by each graph
9
10
Explain 4 Expressing Acceptable Levels with Compound Inequalities
You can express quality-controls levels in real-world problems using compound inequalities
Example 4 Write a compound inequality to represent the indicated quality-control level and graph the solutions
A The recommended pH level for swimming pool water is between 72 and 76 inclusive
Let p be the pH level of swimming pool water
72 is less than or equal to pH level is less than or equal to 76
72 le p le 76
The compound inequality is 72 le p le 76
Graph the solutions
0-10 -8-9 -7-6 -5-4 -3 -2 -1
71 72 73 74 75 76 77 78 79 8070
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 86 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
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oug
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bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
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Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
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oug
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arcourt Publishin
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Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
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oug
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cour
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bik
erid
erlo
nd
onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
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The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
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Elaborate
10 How can you use properties to solve equations with variables on both sides
11 How is a table helpful when constructing equations
12 When solving a real-world problem to find a personrsquos age would a negative solution make sense Explain
13 Essential Question Check-In How do you write an equation to represent a real-world situation
bull Online Homeworkbull Hints and Helpbull Extra Practice
Write an equation for each description
1 The sum of 14 and a number is equal to 17 2 A number increased by 10 is 114
3 The difference between a number and 12 is 20 4 Ten times the sum of half a number and 6 is 8
5 Two-thirds a number plus 4 is 7 6 Tanmayi wants to raise $175 for a school fundraiser She has raised $120 so far How much more does she need to reach her goal
7 Hector is visiting a cousin who lives 350 miles away He has driven 90 miles How many more miles does he need to drive to reach his cousinrsquos home
8 The length of a rectangle is twice its width The perimeter of the rectangle is 126 feet
Evaluate Homework and Practice
Module 2 62 Lesson 2
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Pete
r K
imS
hutt
erst
ock
Write and solve an equation for each situation
9 In one baseball season Peter hit twice the difference of the number of home runs Alice hit and 6 Altogether they hit 18 home runs How many home runs did each player hit that season
10 The perimeter of a parallelogram is 72 meters The width of the parallelogram is 4 meters less than its length Find the length and the width of the parallelogram
11 One month Ruby worked 6 hours more than Isaac and Svetlana worked 4 times as many hours as Ruby Together they worked 126 hours Find the number of hours each person worked
12 In one day Annie traveled 5 times the sum of the number of hours Brian traveled and 2 Together they traveled 20 hours Find the number of hours each person traveled
13 Xian and his cousin Kai both collect stamps Xian has 56 stamps and Kai has 80 stamps The boys recently joined different stamp-collecting clubs Xianrsquos club will send him 12 new stamps per month Kairsquos club will send him 8 new stamps per month After how many months will Xian and Kai have the same number of stamps How many stamps will each have
14 Kenya plans to make a down payment plus monthly payments in order to buy a motorcycle At one dealer she would pay $2500 down and $150 each month At another dealer she would pay $3000 down and $125 each month After how many months would the total amount paid be the same for both dealers What would that amount be
ℓ meters
(ℓ - 4) meters
Module 2 63 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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15 Community Gym charges a $50 membership fee and a $55 monthly fee Workout Gym charges a $200 membership fee and a $45 monthly fee After how many months will the total amount of money paid to both gyms be the same What will the amount be
16 Tina is saving to buy a notebook computer She has two options The first option is to put $200 away initially and save $10 every month The second option is to put $100 away initially and save $30 every month After how many months would Tina save the same amount using either option How much would she save with either option
Use the table to answer each question
Starting Salary Yearly Salary Increase
Company A $24000 $3000
Company B $30000 $2400
Company C $36000 $2000
17 After how many years are the salaries offered by Company A and Company B the same
18 After how many years are the salaries offered by Company B and Company C the same
19 Paul started work at Company B ten years ago at the salary shown in the table At the same time Sharla started at Company C at the salary shown in the table Who earned more during the last year How much more
20 Georgersquos page contains twice as many typed words as Billrsquos page and Billrsquos page contains 50 fewer words than Charliersquos page If each person can type 60 words per minute after one minute the difference between twice the number of words on Billrsquos page and the number of words on Charliersquos page is 210 How many words did Billrsquos page contain initially Use a table to organize the information
Initial number of words
Total number of words after one minute
Module 2 64 Lesson 2
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oug
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cour
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pan
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21 Geometry Sammie bought just enough fencing to border either a rectangular plot or a square plot as shown The perimeters of the plots are the same How many meters of fencing did she buy
HOT Focus on Higher Order Thinking
22 Justify Reasoning Suppose you want to solve the equation 2a + b = 2a where a and b are nonzero real numbers Describe the solution to this equation Justify your description
23 Multi-step A patio in the shape of a rectangle is fenced on all sides with 134 feet of fencing The patio is 5 feet less wide than it is long
a What information can be used to solve the problem How can you find the information
b Describe how to find the area of the patio What is the area of the patio
24 Explain the Error Kevin and Brittany write an equation to represent the following relationship and both students solve their equation Who found the correct equation and solution Why is the other person incorrect
5 times the difference of a number and 20 is the same as half the sum of 4 more than 4 times a number
Kevin Brittany
5 (x - 20) = 1 _ 2 (4x + 4) 5 (20 + x) = 1 _ 2 (4x + 4)
5x - 100 = 2x + 2 100 - 5x = 2x + 2
3x - 100 = 2 100 - 7x = 2
3x = 102 -7x = -98
x = 34 x = 14
(3x + 2) meters
(x + 2) meters
(x + 2) meters
(x - 1) meters
ℓ feet
(ℓ - 5) feet
Module 2 65 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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25 What If Alexa and Zack are solving the following problem
The number of miles on Car A is 50 miles more than the number of miles on Car B and the number of miles on Car B is 30 miles more than the number of miles on Car C All the cars travel 50 miles in 1 hour After 1 hour twice the number of miles on Car A is 70 miles less than 3 times the number of miles on Car C How many miles were there on Car B initially
Alexa assumes there are m miles on Car B Zack assumes there are m miles on Car C Will Zackrsquos answer be the same as Alexarsquos answer Explain
Lesson Performance Task
Stacy Oliver and Jivesh each plan to put a certain amount of money into their savings accounts that earn simple interest of 6 per year Stacy puts $550 more than Jivesh and Oliver puts in 2 times as much as Jivesh After a year the amount in Stacyrsquos account is 2 times the sum of $212 and the amount in Oliverrsquos account How much does each person initially put into his or her account Who had the most money in his or her account after a year Who had the least Explain
Zackrsquos Table Initial Miles
Miles after One Hour
Alexarsquos Table Initial Miles
Miles after One Hour
Amount in Account Initially Amount in Account after One Year
Module 2 66 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
hton
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cour
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pan
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Name Class Date
Resource Locker
Explore Rearranging Mathematical FormulasLiteral Equations are equations that contain two or more variables There are many literal equations in the form of math science and engineering formulas These formulas may seem like they can only be solved for the variable that is isolated on one side of the formula By using inverse operations and the properties of equality a formula can be rearranged so any variable in the formula can be isolated It is no different than how equations are solved by using inverse operations and the properties of equality
How can you solve the equation 42 = 6x
A42 _ = 6x _ What is the reason for dividing
Why divide by
= x By rearranging the equation x was isolated and the solution was found
The mathematical formula for the volume of a rectangular prism B = Vh or V = ℓwh is a literal equation V represents volume ℓ represents length w represents width and h represents height Using inverse operations the formula can be rearranged to solve for any one of the variables that might be unknown Like solving for x a formula can be rearranged to isolate a variable
B In the formula V = ℓwh the variable h needs to be isolated
The operation of is used in the formula The inverse
operation should be used
to isolate
C V _____ = ℓwh _____
V _ =
The formula rearranged in this way can easily produce the height of the rectangular prism when the volume length and width are known
Reflect
1 Using the formula for a rectangular prism rewrite the formula to solve for ℓ
ℓw
h
Module 2 67 Lesson 3
23 Solving for a VariableEssential Question How do you rewrite formulas and literal equations
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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Photo
grap
hyAurora Ph
otosCorb
is
Explain 1 Rearranging Scientific FormulasUse inverse operations to isolate the unknown variable in a scientific formula
The formula for density is D = m __ V Lead has a very high density of 11340 kg m 3 Plastic foam has a very low density of 75 kg m 3 The formula for density can be rearranged to solve for V volume or m mass
Example 1
A A sinker on a fishing line is made of lead and has a volume of 0000015 m 3 What is the mass of the sinker
The density formula can be rearranged to isolate m the mass The values for volume and density can then be substituted into the formula to find the mass
D = m _ V
DV = ( m _ V ) V DV = m
(11340 kg m 3 ) (0000015 m 3 ) = m
017 kg asymp m
B The design for a life preserver requires 03 kilogram of plastic foam to provide proper buoyancy What is the volume of the plastic foam required
Rearrange the density formula to isolate V
D = m _ V
(D) V = m _ V
DV =
DV _ = m _
V =
Now substitute the given values
V = _
V = m 3
Your Turn
2 For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Determine the altitude in feet when t is -275 ∘F and g is 60 ∘F
Module 2 68 Lesson 3
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Explain 2 Rearranging Literal EquationsUsing inverse operations to rearrange literal equations can be applied to any formula The interest formula I = prt is another example of a literal equation In the formula I represents interest p the principal or the initial amount to which interest will be applied r the rate at which interest will be paid and t is the time in years
Example 2
A Find the number of years used in the calculation of a $1000 loan at an interest rate of 5 with interest totaling $600
Solve the formula for t
I = prt
I _ pr = prt
_ pr
I _ pr = t
Substitute the given values Since the interest rate is 5 r = 005$600 __
$1000 middot 005 = t
12 = t
So the length of time for the loan is 12 years
B Determine the interest rate for a $2000 loan that will be paid off in 4 years with interest totaling $640 In order to find the interest rate solve the formula for r
I = prt
I _ = prt _
_ = r
Now substitute the values and simplify
__
( ) ( ) = r
008 = r
So the interest rate is per year
Your Turn
3 The formula y = mx + b is the slope-intercept form of the equation of a line Solve the equation for m
Module 2 69 Lesson 3
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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oug
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bull Online Homeworkbull Hints and Helpbull Extra Practice
Solve for the indicated variable in each mathematical formula
1 C = 2πr for r 2 A = 1 __ 2 bh for b 3 y = mx + b for x
4 A = 1 __ 2 (a + b)h for h 5 V = πr2h for h 6 SA = 2πr2 + 2πrh for h
Solve for the indicated variable in each scientific formula
7 d = rt for t 8 PV = nRT for T
9 A = FV - OV _______ T for OV 10 C = Wtc _ 1000 for W
Evaluate Homework and Practice
Elaborate
4 Discussion What could be a reason for isolating a variable in a literal equation
5 Describe a situation in which a formula could be used more easily if it were rearranged Include the formula in your description
6 Essential Question Check-In How do you isolate a variable
Module 2 70 Lesson 3
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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cour
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pan
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cean
C
orb
is
Solve for the indicated variable in each literal equation
11 2p + 5r = q for p 12 -10 = xy + z for x 13 a __ b = c for b
14 h - 4 _ j = k for j 15 x __ 5 - g = a for x 16 5p + 9c = p for c
17 2 __ 5 (z + 1) = y for z 18 g (h + 2 __ 3 ) = 1 for h 19 a(n - 3) + 8 = bn for n
20 Which is a possible way to rewrite the equation y = 3x + 3b to solve for b
A b = y - 3x
_ 3 C b = y - 3
_____ 3x
B b = 3(y - 3x) D b = x(y - 3)
21 Sports To find a baseball pitcherrsquos earned run average (ERA) you can use the formula Ei = 9r in which E represents ERA i represents the number of innings pitched and r represents the number of earned runs allowed Solve the equation for E What is a pitcherrsquos ERA if he allows 5 earned runs in 18 innings pitched
22 Meteorology For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Solve the equation for a If the atmospheric temperature is -655 ∘F and the ground temperature is 57 ∘F what is the altitude
Module 2 71 Lesson 3
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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arcourt Publishin
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Rand
y D
uch
aineA
lamy
HOT Focus on Higher Order Thinking
23 Explain the Error A student was asked to use the formula for the perimeter of a rectangle P = 2ℓ + 2w to solve for ℓ The student came up with an answer P - 2w = 2ℓ What error did the student make Explain Then solve for ℓ
24 Multi-Step The formula c = 5p + 215 relates c the total cost in dollars of hosting a birthday party at a skating rink to p the number of people attending If Alliersquos parents are willing to spend $300 for a party how many people can attend
25 Multi-Step The formula for the area of a triangle is A = 1 __ 2 bh in which b represents the length of thebase and h represents the height If a triangle has an area of 192 mm2 and the height is 12 mm what is the measure of the base
Lesson Performance TaskThe following table shows the average low temperatures in Fahrenheit for the city of Boston for several months during the year The formula F = 9 __ 5 C + 32 allows you to determine the temperature in Fahrenheit when given the temperature in Celsius
MonthTemperature in
FahrenheitTemperature in
Celsius
January 22deg
April 41deg
July 65deg
October 47deg
December 28deg
a Use the information given to determine the average low temperatures in Celsius
b Would it ever be possible for the temperature in Celsius to have a greater value than the temperature in Fahrenheit Explain why or why not
Module 2 72 Lesson 3
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
Name Class Date
Resource Locker
copy H
oug
hton
Mif
flin
Har
cour
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Com
pan
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mag
e cr
edit
s copy
Patr
ick
Lan
eSo
mos
Imag
esC
orb
is
Explore Creating Inequalities from Verbal DescriptionsAn inequality is a statement that compares two expressions that are not strictly equal by using one of the following inequality signs
Symbol Meaning
lt is less than
le is less than or equal to
gt is greater than
ge is greater than or equal to
ne is not equal to
You have probably seen a sign at an amusement park saying something like ldquoYou must be at least 48 inches tall to ride this riderdquo This statement could be written as h ge 48 in where h represents the height of a person allowed to ride
Nora is planning a birthday party for her little sister Colleen Norarsquos budget will allow her to spend no more than $50 for party supplies Eight children including Colleen will attend the party and Nora wants to determine how much she could spend on party favors for each child She will also purchase a cake for $10 Write an inequality that represents the situation and find possible solutions
A First let c represent the cost of a party favor for each child Write an expression for the total cost of the party as a function of c
c +
B Which inequality symbol should be used to represent the phrase ldquono more thanrdquo
C Write the inequality that represents Norarsquos budget goal
8c + 10 le
D Suppose Nora finds party favors that cost $4 each Use a value of 4 for c and check to see if this inequality is true
8 middot 4 + 10 le 50
le 50
Module 2 73 Lesson 4
24 Creating and Solving Inequalities
Essential Question How do you write and solve an inequality that represents a real-world situation
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
arcourt Publishin
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pany
Is the inequality true
Could Nora buy $6 party favors for all of her guests without going over budget
Reflect
1 Why does an inequality represent Norarsquos budget calculation better than an equation
2 The solution set of an inequality consists of all values that make the statement true Describe the whole dollar amounts that are in the solution set for this situation
Explain 1 Creating and Solving Inequalities Involving the Distributive Property
You may need to use the Distributive Property before you can solve an inequality
Distributive Property If a b and c are real numbers then a(b + c) = ab + ac
The inequality sign must be reversed when multiplying or dividing both sides of an inequality by a negative number
Example 1
A Trina is buying 12 shirts for the drama club She will choose a style for the blank shirts and then pay an additional charge of $275 for each shirt to have the club logo If Trina cannot spend more than $99 how much can she spend on each blank shirt Write and solve an inequality to find the possible cost of each blank shirt
Let s represent the cost of each blank shirt
Write an inequality to represent the situation 12(s + 275) le 99
Use the Distributive Property 12s + 33 le 99
Subtraction Property of Inequality 12s + 33 - 33 le 99 - 33
Simplify 12s le 66
Division Property of Inequality 12s ___ 12 le 66 __ 12
Simplify s le 55
Module 2 74 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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oug
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Mif
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Har
cour
t Pub
lishi
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Com
pan
y
Check your answer
Since s le 55 check a smaller number 12(5 + 275) le 99
Trina can order blank shirts that cost $550 or less 93 le 99 true
B Sergio needs to buy gifts for 8 friends He wants to give the same gift to all his friends and he plans to have the gifts wrapped for an additional charge of $150 each If Sergio spends at least $70 he will receive free shipping on his order Write and solve an inequality to determine how much Sergio needs to spend on each gift in order to receive free shipping
Let g be the cost of one gift
Write an inequality to represent the situation ( g + ) ge 70
Use the Distributive Property g + ge 70
Subtraction Property of Inequality g + 12 - ge 70 -
Simplify 8g ge
Division Property of Inequality 8g _
ge 58 _
Simplify g ge
Check your answer
Since g ge 725 check a larger number 8(8 + 150) ge 70
Sergio must spend at least on each gift ge 70
Reflect
3 Discussion Why is the first step in solving the inequality to use the Distributive Property instead of working inside the parentheses
Your Turn
4 Zachary is planning to send a video game to each of his two brothers If he buys the same game for both brothers and pays $475 to ship each game how much can he spend on each game without spending more than $100 Write and solve an inequality for this situation
Solve each inequality
5 4 _ 3 (6x + 9) lt 4 6 -2 ( 1 _ 4 x + 2 ) ge 5
Module 2 75 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany
Explain 2 Creating and Solving Inequalities with Variables on Both Sides
Some inequalities have variable terms on both sides of the inequality symbol You can solve these inequalities the same way you solved equations with variables on both sides Use the properties of inequality to collect all the variable terms on one side and all the constant terms on the other side
Example 2
A The Daily Info charges a fee of $650 plus $80 per week to run an ad The Peoplersquos Paper charges $145 per week For how many weeks must an ad run for the total cost at the Daily Info to be less expensive than the cost at the Peoplersquos Paper Let w be the number of weeks the ad runs in the paper
Write an inequality to represent the situation 650 + 80w lt 145w
Subtraction Property of Inequality 650 + 80w - 80w lt 145w - 80w
Simplify 650 lt 65w
Division Property of Inequality 650 _ 65 lt 65w _ 65
Simplify 10 lt w
The total cost at the Daily Info is less than the cost at the Peoplersquos Paper if the ad runs for more than 10 weeks
B The Home Cleaning Company charges $312 to power-wash the siding of a house plus $12 for each window Power Clean charges $36 per window and the price includes power-washing the siding How many windows must a house have to make the total cost from The Home Cleaning Company less expensive than Power Clean Let w be the number of windows
Write an inequality to represent the situation +12w lt 36w
Subtraction Property of Inequality 312 + 12w - lt 36w -
Simplify 312 lt
Division Property of Inequality 312 _ lt 24w _
Simplify lt w
A house must have more than 13 windows for The Home Cleaning Company to be less expensive than Power Clean
Reflect
7 How would the final inequality change if you divided by ndash24 in the next to last step
Your Turn
8 The school band will sell pizzas to raise money for new uniforms The supplier charges $100 plus $4 per pizza The band members sell the pizzas for $7 each Write and solve an inequality to find how many pizzas the band members will have to sell to make a profit
Module 2 76 Lesson 4
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Elaborate
9 Which inequality symbol would you use to represent the following words or phrases Can you come up with more examples
a at most b farther than c younger than d up to
10 Discussion How are the steps to solving an inequality similar to those for solving an equation How are they different
11 Essential Question Check-In How can you write an inequality that represents a real-world situation
Write an inequality that represents the description and then solve
1 Max has more than 5 carrots (number of carrots Max has = c)
2 Brigitte is shorter than 5 feet (Brigittersquos height = h)
3 Twice a number (x) is less than 10 4 Six more than five times a number (x) is at least twenty-one
5 Dave has $15 to spend on an $8 book and two birthday cards (c) for his friends How much can he spend on each card if he buys the same card for each friend
6 Toni can carry up to 18 lb in her backpack Her lunch weighs 1 lb her gym clothes weigh 2 lb and her books (b) weigh 3 lb each How many books can she carry in her backpack
Evaluate Homework and Practice
bull Online Homeworkbull Hints and Helpbull Extra Practice
Module 2 77 Lesson 4
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pany
Solve each inequality
7 3 (x - 2) gt -3 8 5 + 5 (x + 4) le 20 9 3 + 1 _ 2 (3 - x) lt -7
10 3 (x + 6) - 2 (x + 2) ge 10 11 5 (3 - x) -4 (2 - 3x) gt 2 12 1 _ 2 (4x - 2) - 2 _ 3 (6x + 9) le 4
13 x + 1 gt -5 (7 - 2x) 14 5 _ 3 (6x + 3) le 2x - 7
15 2x le - 2 __ 3 (4x + 4) 16 1 __ 2 (-2x - 10) gt 3 (4 - 6x)
17 -5 - 3x ge 2 (10 + 2x) + 3 18 -3 (9x + 20) ge 15x - 20
19 8 ( 1 _ 4 x - 3) + 24 lt 4 ( x + 5 ) 20 6x - 2 (x + 2) gt 2 - 3 (x + 3)
Module 2 78 Lesson 4
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21 Physics A crane cable can support a maximum load of 15000 kg If a bucket has a mass of 2000 kg and gravel has a mass of 1500 kg for every cubic meter how many cubic meters of gravel (g) can be safely lifted by the crane
22 Find the solution set of each inequality below and then determine which inequalities have the same solution set as 1 _ 3 ( -5x - 3 ) lt 14
a 1 _ 3 (5x + 3) gt -14 b 2 _ 5 (10x + 20) gt 44
c - 2 _ 5 (10x + 20) lt -44 d - 1 _ 3 (5x + 3) lt 14
e 2 _ 5 (10x - 20) gt -44 f 1 _ 3 (5x + 3) lt -14
HOT Focus on Higher Order Thinking
23 Explain the Error Sven is trying to find the maximum amount of time he can spend practicing the five scales of piano music he is supposed to be working on He has 60 minutes to practice piano and would like to spend at least 35 minutes playing songs instead of practicing scales So Sven sets up the following inequality where t is the number of minutes he spends on each scale and solves it
60 - 5t le 35-5t le -25
t ge 5
Sven has concluded that he should spend 5 minutes or more on each scale Is this correct If not what mistake did he make Then solve for the correct answer
Module 2 79 Lesson 4
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24 Critical Thinking Anika wants to determine the maximum number of tulip bulbs (t) she can purchase if each bulb costs $150 She will also need to purchase separate pots for each bulb at $125 each and a bag of potting soil for $1000 Set up an inequality to determine how many tulip bulbs Anika can purchase without spending more than $2000 and solve it Can Anika buy exactly enough bulbs and pots to spend the full $2000 Explain Can you think of a better inequality to describe the answer
25 Geometry The area of the triangle shown is no more than 10 square inches
a Write an inequality that can be used to find x
b Solve the inequality from part a c What is the maximum height of the triangle
Lesson Performance TaskWhen planning an airplane route the trip planner must be careful to consider the range the aircraft can travel and the availability of airports to stop and refuel
A large commercial jet airplane burns approximately 5 gallons of fuel per mile flown plus about 8500 gallons of fuel per trip to reach cruising altitude With a useable fuel capacity of 50000 gallons (there is additional fuel reserved for emergencies) describe the acceptable distance for which an airline could establish a non-stop flight
For flights originating from Chicago determine which cities could be safely reached by a non-stop flight
City Distance from Chicago (miles)
Bangalore India 8530
Jakarta Indonesia 9810
Johannesburg South Africa 8680
Moscow Russia 4970
Paris France 4130
Perth Australia 10970
Tokyo Japan 6300
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oug
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eva O
lesiaShutterstock
(2x - 3) in
4 in
Module 2 80 Lesson 4
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Name Class Date
Resource Locker
Explore Truth Tables and Compound StatementsA compound statement is formed by combining two or more simple statements A compound statement can be true or false A compound statement involving AND is true when both simple statements are true A compound statement involving OR is true when either one simple statement or both are true
A Complete the truth table
P QP
True or FalseQ
True or FalseP AND Q
True or False
A dog is a mammal Red is a color
A dog is a mammal Red is not a color
A dog is a fish Red is a color
A dog is a fish Red is not a color
B P AND Q is true when
C Complete the truth table
P QP
True or FalseQ
True or FalseP OR Q
True or False
1 is an odd number 2 is an even number
1 is an odd number 2 is an odd number
1 is an even number 2 is an even number
1 is an even number 2 is an odd number
D P OR Q is true when
Reflect
1 Give two simple statements P and Q for which P AND Q is false and P OR Q is true
Module 2 81 Lesson 5
25 Creating and Solving Compound Inequalities
Essential Question How can you solve a compound inequality and graph the solution set
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Explain 1 Solving Compound Inequalities Involving ANDCombining two or more simple inequalities forms a compound inequality The graph of a compound inequality involving AND is the intersection or the overlapping region of the simple inequality graphs
Compound Inequalities AND
Words Algebra Graph
All real numbers greater than 2AND less than 6
x gt 2 AND x lt 62 lt x lt 6
All real numbers greater than or equal to 2 AND less than or equal to 6
x ge 2 AND x le 62 le x le 6
Example 1 Solve each compound inequality and graph the solutions
A 4 le x + 2 le 8
4 le x + 2 AND x + 2 le 8 Write the compound inequality using AND
4 - 2 le x + 2 - 2 x + 2 - 2 le 8 - 2 Subtract 2 from both sides of each simple inequality
2 le x x le 6 Simplify
Graph 2 le x
Graph x le 6
Graph the intersection by finding where the two graphs overlap
B -5 le 2x + 3 lt 9
-5 - le 2x + 3 - lt 9 - Subtract from each part of the inequality
le 2x lt Simplify
-8 _ le 2x _ lt 6 _ Divide each part of the inequality by
le x lt Simplify
Graph -4 le x
Graph x lt 3
Graph the intersection by finding where the two graphs overlap -1 0 1 2 3 4 5-5-4 -3 -2
0 2 4 6 8 10 12-8-6-4 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 82 Lesson 5
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Reflect
2 Discussion Explain why 2 le x le 6 can be considered the short method for writing the AND compound inequality x ge 2 AND x le 6
YourTurn
Solve each compound inequality and graph the solutions
3 -2 lt x - 3 lt 5
4 -10 lt 3x + 2 le 8
Explain 2 Solving Compound Inequalities Involving ORThe graph of a compound inequality involving OR is the union or the combined region of the simple inequality graphs
Compound Inequalities OR
Words Algebra Graph
All real numbers less than 2OR greater than 6
x lt 2 OR x gt 6
All real numbers less than or equal to 2OR greater than or equal to 6
x le 2 OR x ge 6
-1 0 1 2 3 4 5-5-4 -3 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 83 Lesson 5
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Example 2 Solve each compound inequality and graph the solutions
A -4 + x gt 1 OR -4 + x lt -3
-4 + x gt 1 OR -4 + x lt -3 Write the compound inequality using OR
-4 + 4 + x gt 1 + 4 -4 + 4 + x lt -3 + 4 Add 4 to both sides of each simple inequality
x gt 5 x lt 1 Simplify
Graph x gt 5
Graph x lt 1
Graph the union by combining the graphs
B 2x le 6 OR 3x gt 12
2x le 6 OR 3x gt 12 Write the compound inequality using OR
2x _ le 6 _ OR 3x _ gt 12 _ Divide the first simple inequality by
x le OR x gt
Graph x le 3
Graph x gt 4
Graph the union by combining the graphs
Reflect
5 Critical Thinking What kind of compound inequality has no solution
Divide the second simple inequality by
Simplify
0 1 2 3 4 5 6-4 -3 -2 -1
-0 1 2 3 4 5 6-4 -3 -2 -1
Module 2 84 Lesson 5
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oug
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Your Turn
Solve each compound inequality and graph the solutions
6 x - 5 ge -2 OR x -5 le -6
7 4x -1 lt 15 OR 8x ge 48
Explain 3 Creating Compound Inequalities From GraphsGiven a number line graph with a solution set graphed you can create a compound inequality to fit the graph
Example 3 Write the compound inequality shown by each graph
A
The shaded portion of the graph is not between two values so the compound inequality involves OR
On the left the graph shows an arrow pointing left from -1 and a solid circle so use le
The inequality is x le -1
On the right the graph shows an arrow pointing right from 7 and a solid circle so use ge
The inequality is x ge 7
The compound inequality is x le -1 OR x ge 7
B
The graph is shaded between the values and so the compound inequality involves AND
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The compound inequality is
-1 0 1 2 3 4 5-5-4 -3 -2
4 5 6 7 8 9 100 1 2 3
2 3 4 5 6 7 8-2 -1 0 1
10 2 3 4 5 6 7 8 9-1
Module 2 85 Lesson 5
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oug
hton Mifflin H
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Reflect
8 What is a short method to write the compound inequality x ge 0 AND x lt 6
Your Turn
Write the compound inequality shown by each graph
9
10
Explain 4 Expressing Acceptable Levels with Compound Inequalities
You can express quality-controls levels in real-world problems using compound inequalities
Example 4 Write a compound inequality to represent the indicated quality-control level and graph the solutions
A The recommended pH level for swimming pool water is between 72 and 76 inclusive
Let p be the pH level of swimming pool water
72 is less than or equal to pH level is less than or equal to 76
72 le p le 76
The compound inequality is 72 le p le 76
Graph the solutions
0-10 -8-9 -7-6 -5-4 -3 -2 -1
71 72 73 74 75 76 77 78 79 8070
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 86 Lesson 5
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oug
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B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
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oug
hton Mifflin H
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pany
bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
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oug
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Com
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Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
arcourt Publishin
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pany bull Im
age C
redits copy
Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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Mif
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Har
cour
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Com
pan
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mag
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bik
erid
erlo
nd
onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
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Mif
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Har
cour
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Com
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mag
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(t)copy
Pete
r K
imS
hutt
erst
ock
Write and solve an equation for each situation
9 In one baseball season Peter hit twice the difference of the number of home runs Alice hit and 6 Altogether they hit 18 home runs How many home runs did each player hit that season
10 The perimeter of a parallelogram is 72 meters The width of the parallelogram is 4 meters less than its length Find the length and the width of the parallelogram
11 One month Ruby worked 6 hours more than Isaac and Svetlana worked 4 times as many hours as Ruby Together they worked 126 hours Find the number of hours each person worked
12 In one day Annie traveled 5 times the sum of the number of hours Brian traveled and 2 Together they traveled 20 hours Find the number of hours each person traveled
13 Xian and his cousin Kai both collect stamps Xian has 56 stamps and Kai has 80 stamps The boys recently joined different stamp-collecting clubs Xianrsquos club will send him 12 new stamps per month Kairsquos club will send him 8 new stamps per month After how many months will Xian and Kai have the same number of stamps How many stamps will each have
14 Kenya plans to make a down payment plus monthly payments in order to buy a motorcycle At one dealer she would pay $2500 down and $150 each month At another dealer she would pay $3000 down and $125 each month After how many months would the total amount paid be the same for both dealers What would that amount be
ℓ meters
(ℓ - 4) meters
Module 2 63 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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pany
15 Community Gym charges a $50 membership fee and a $55 monthly fee Workout Gym charges a $200 membership fee and a $45 monthly fee After how many months will the total amount of money paid to both gyms be the same What will the amount be
16 Tina is saving to buy a notebook computer She has two options The first option is to put $200 away initially and save $10 every month The second option is to put $100 away initially and save $30 every month After how many months would Tina save the same amount using either option How much would she save with either option
Use the table to answer each question
Starting Salary Yearly Salary Increase
Company A $24000 $3000
Company B $30000 $2400
Company C $36000 $2000
17 After how many years are the salaries offered by Company A and Company B the same
18 After how many years are the salaries offered by Company B and Company C the same
19 Paul started work at Company B ten years ago at the salary shown in the table At the same time Sharla started at Company C at the salary shown in the table Who earned more during the last year How much more
20 Georgersquos page contains twice as many typed words as Billrsquos page and Billrsquos page contains 50 fewer words than Charliersquos page If each person can type 60 words per minute after one minute the difference between twice the number of words on Billrsquos page and the number of words on Charliersquos page is 210 How many words did Billrsquos page contain initially Use a table to organize the information
Initial number of words
Total number of words after one minute
Module 2 64 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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21 Geometry Sammie bought just enough fencing to border either a rectangular plot or a square plot as shown The perimeters of the plots are the same How many meters of fencing did she buy
HOT Focus on Higher Order Thinking
22 Justify Reasoning Suppose you want to solve the equation 2a + b = 2a where a and b are nonzero real numbers Describe the solution to this equation Justify your description
23 Multi-step A patio in the shape of a rectangle is fenced on all sides with 134 feet of fencing The patio is 5 feet less wide than it is long
a What information can be used to solve the problem How can you find the information
b Describe how to find the area of the patio What is the area of the patio
24 Explain the Error Kevin and Brittany write an equation to represent the following relationship and both students solve their equation Who found the correct equation and solution Why is the other person incorrect
5 times the difference of a number and 20 is the same as half the sum of 4 more than 4 times a number
Kevin Brittany
5 (x - 20) = 1 _ 2 (4x + 4) 5 (20 + x) = 1 _ 2 (4x + 4)
5x - 100 = 2x + 2 100 - 5x = 2x + 2
3x - 100 = 2 100 - 7x = 2
3x = 102 -7x = -98
x = 34 x = 14
(3x + 2) meters
(x + 2) meters
(x + 2) meters
(x - 1) meters
ℓ feet
(ℓ - 5) feet
Module 2 65 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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25 What If Alexa and Zack are solving the following problem
The number of miles on Car A is 50 miles more than the number of miles on Car B and the number of miles on Car B is 30 miles more than the number of miles on Car C All the cars travel 50 miles in 1 hour After 1 hour twice the number of miles on Car A is 70 miles less than 3 times the number of miles on Car C How many miles were there on Car B initially
Alexa assumes there are m miles on Car B Zack assumes there are m miles on Car C Will Zackrsquos answer be the same as Alexarsquos answer Explain
Lesson Performance Task
Stacy Oliver and Jivesh each plan to put a certain amount of money into their savings accounts that earn simple interest of 6 per year Stacy puts $550 more than Jivesh and Oliver puts in 2 times as much as Jivesh After a year the amount in Stacyrsquos account is 2 times the sum of $212 and the amount in Oliverrsquos account How much does each person initially put into his or her account Who had the most money in his or her account after a year Who had the least Explain
Zackrsquos Table Initial Miles
Miles after One Hour
Alexarsquos Table Initial Miles
Miles after One Hour
Amount in Account Initially Amount in Account after One Year
Module 2 66 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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Name Class Date
Resource Locker
Explore Rearranging Mathematical FormulasLiteral Equations are equations that contain two or more variables There are many literal equations in the form of math science and engineering formulas These formulas may seem like they can only be solved for the variable that is isolated on one side of the formula By using inverse operations and the properties of equality a formula can be rearranged so any variable in the formula can be isolated It is no different than how equations are solved by using inverse operations and the properties of equality
How can you solve the equation 42 = 6x
A42 _ = 6x _ What is the reason for dividing
Why divide by
= x By rearranging the equation x was isolated and the solution was found
The mathematical formula for the volume of a rectangular prism B = Vh or V = ℓwh is a literal equation V represents volume ℓ represents length w represents width and h represents height Using inverse operations the formula can be rearranged to solve for any one of the variables that might be unknown Like solving for x a formula can be rearranged to isolate a variable
B In the formula V = ℓwh the variable h needs to be isolated
The operation of is used in the formula The inverse
operation should be used
to isolate
C V _____ = ℓwh _____
V _ =
The formula rearranged in this way can easily produce the height of the rectangular prism when the volume length and width are known
Reflect
1 Using the formula for a rectangular prism rewrite the formula to solve for ℓ
ℓw
h
Module 2 67 Lesson 3
23 Solving for a VariableEssential Question How do you rewrite formulas and literal equations
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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Photo
grap
hyAurora Ph
otosCorb
is
Explain 1 Rearranging Scientific FormulasUse inverse operations to isolate the unknown variable in a scientific formula
The formula for density is D = m __ V Lead has a very high density of 11340 kg m 3 Plastic foam has a very low density of 75 kg m 3 The formula for density can be rearranged to solve for V volume or m mass
Example 1
A A sinker on a fishing line is made of lead and has a volume of 0000015 m 3 What is the mass of the sinker
The density formula can be rearranged to isolate m the mass The values for volume and density can then be substituted into the formula to find the mass
D = m _ V
DV = ( m _ V ) V DV = m
(11340 kg m 3 ) (0000015 m 3 ) = m
017 kg asymp m
B The design for a life preserver requires 03 kilogram of plastic foam to provide proper buoyancy What is the volume of the plastic foam required
Rearrange the density formula to isolate V
D = m _ V
(D) V = m _ V
DV =
DV _ = m _
V =
Now substitute the given values
V = _
V = m 3
Your Turn
2 For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Determine the altitude in feet when t is -275 ∘F and g is 60 ∘F
Module 2 68 Lesson 3
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Explain 2 Rearranging Literal EquationsUsing inverse operations to rearrange literal equations can be applied to any formula The interest formula I = prt is another example of a literal equation In the formula I represents interest p the principal or the initial amount to which interest will be applied r the rate at which interest will be paid and t is the time in years
Example 2
A Find the number of years used in the calculation of a $1000 loan at an interest rate of 5 with interest totaling $600
Solve the formula for t
I = prt
I _ pr = prt
_ pr
I _ pr = t
Substitute the given values Since the interest rate is 5 r = 005$600 __
$1000 middot 005 = t
12 = t
So the length of time for the loan is 12 years
B Determine the interest rate for a $2000 loan that will be paid off in 4 years with interest totaling $640 In order to find the interest rate solve the formula for r
I = prt
I _ = prt _
_ = r
Now substitute the values and simplify
__
( ) ( ) = r
008 = r
So the interest rate is per year
Your Turn
3 The formula y = mx + b is the slope-intercept form of the equation of a line Solve the equation for m
Module 2 69 Lesson 3
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bull Online Homeworkbull Hints and Helpbull Extra Practice
Solve for the indicated variable in each mathematical formula
1 C = 2πr for r 2 A = 1 __ 2 bh for b 3 y = mx + b for x
4 A = 1 __ 2 (a + b)h for h 5 V = πr2h for h 6 SA = 2πr2 + 2πrh for h
Solve for the indicated variable in each scientific formula
7 d = rt for t 8 PV = nRT for T
9 A = FV - OV _______ T for OV 10 C = Wtc _ 1000 for W
Evaluate Homework and Practice
Elaborate
4 Discussion What could be a reason for isolating a variable in a literal equation
5 Describe a situation in which a formula could be used more easily if it were rearranged Include the formula in your description
6 Essential Question Check-In How do you isolate a variable
Module 2 70 Lesson 3
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mag
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copyO
cean
C
orb
is
Solve for the indicated variable in each literal equation
11 2p + 5r = q for p 12 -10 = xy + z for x 13 a __ b = c for b
14 h - 4 _ j = k for j 15 x __ 5 - g = a for x 16 5p + 9c = p for c
17 2 __ 5 (z + 1) = y for z 18 g (h + 2 __ 3 ) = 1 for h 19 a(n - 3) + 8 = bn for n
20 Which is a possible way to rewrite the equation y = 3x + 3b to solve for b
A b = y - 3x
_ 3 C b = y - 3
_____ 3x
B b = 3(y - 3x) D b = x(y - 3)
21 Sports To find a baseball pitcherrsquos earned run average (ERA) you can use the formula Ei = 9r in which E represents ERA i represents the number of innings pitched and r represents the number of earned runs allowed Solve the equation for E What is a pitcherrsquos ERA if he allows 5 earned runs in 18 innings pitched
22 Meteorology For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Solve the equation for a If the atmospheric temperature is -655 ∘F and the ground temperature is 57 ∘F what is the altitude
Module 2 71 Lesson 3
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Rand
y D
uch
aineA
lamy
HOT Focus on Higher Order Thinking
23 Explain the Error A student was asked to use the formula for the perimeter of a rectangle P = 2ℓ + 2w to solve for ℓ The student came up with an answer P - 2w = 2ℓ What error did the student make Explain Then solve for ℓ
24 Multi-Step The formula c = 5p + 215 relates c the total cost in dollars of hosting a birthday party at a skating rink to p the number of people attending If Alliersquos parents are willing to spend $300 for a party how many people can attend
25 Multi-Step The formula for the area of a triangle is A = 1 __ 2 bh in which b represents the length of thebase and h represents the height If a triangle has an area of 192 mm2 and the height is 12 mm what is the measure of the base
Lesson Performance TaskThe following table shows the average low temperatures in Fahrenheit for the city of Boston for several months during the year The formula F = 9 __ 5 C + 32 allows you to determine the temperature in Fahrenheit when given the temperature in Celsius
MonthTemperature in
FahrenheitTemperature in
Celsius
January 22deg
April 41deg
July 65deg
October 47deg
December 28deg
a Use the information given to determine the average low temperatures in Celsius
b Would it ever be possible for the temperature in Celsius to have a greater value than the temperature in Fahrenheit Explain why or why not
Module 2 72 Lesson 3
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Name Class Date
Resource Locker
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oug
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pan
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mag
e cr
edit
s copy
Patr
ick
Lan
eSo
mos
Imag
esC
orb
is
Explore Creating Inequalities from Verbal DescriptionsAn inequality is a statement that compares two expressions that are not strictly equal by using one of the following inequality signs
Symbol Meaning
lt is less than
le is less than or equal to
gt is greater than
ge is greater than or equal to
ne is not equal to
You have probably seen a sign at an amusement park saying something like ldquoYou must be at least 48 inches tall to ride this riderdquo This statement could be written as h ge 48 in where h represents the height of a person allowed to ride
Nora is planning a birthday party for her little sister Colleen Norarsquos budget will allow her to spend no more than $50 for party supplies Eight children including Colleen will attend the party and Nora wants to determine how much she could spend on party favors for each child She will also purchase a cake for $10 Write an inequality that represents the situation and find possible solutions
A First let c represent the cost of a party favor for each child Write an expression for the total cost of the party as a function of c
c +
B Which inequality symbol should be used to represent the phrase ldquono more thanrdquo
C Write the inequality that represents Norarsquos budget goal
8c + 10 le
D Suppose Nora finds party favors that cost $4 each Use a value of 4 for c and check to see if this inequality is true
8 middot 4 + 10 le 50
le 50
Module 2 73 Lesson 4
24 Creating and Solving Inequalities
Essential Question How do you write and solve an inequality that represents a real-world situation
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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pany
Is the inequality true
Could Nora buy $6 party favors for all of her guests without going over budget
Reflect
1 Why does an inequality represent Norarsquos budget calculation better than an equation
2 The solution set of an inequality consists of all values that make the statement true Describe the whole dollar amounts that are in the solution set for this situation
Explain 1 Creating and Solving Inequalities Involving the Distributive Property
You may need to use the Distributive Property before you can solve an inequality
Distributive Property If a b and c are real numbers then a(b + c) = ab + ac
The inequality sign must be reversed when multiplying or dividing both sides of an inequality by a negative number
Example 1
A Trina is buying 12 shirts for the drama club She will choose a style for the blank shirts and then pay an additional charge of $275 for each shirt to have the club logo If Trina cannot spend more than $99 how much can she spend on each blank shirt Write and solve an inequality to find the possible cost of each blank shirt
Let s represent the cost of each blank shirt
Write an inequality to represent the situation 12(s + 275) le 99
Use the Distributive Property 12s + 33 le 99
Subtraction Property of Inequality 12s + 33 - 33 le 99 - 33
Simplify 12s le 66
Division Property of Inequality 12s ___ 12 le 66 __ 12
Simplify s le 55
Module 2 74 Lesson 4
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Check your answer
Since s le 55 check a smaller number 12(5 + 275) le 99
Trina can order blank shirts that cost $550 or less 93 le 99 true
B Sergio needs to buy gifts for 8 friends He wants to give the same gift to all his friends and he plans to have the gifts wrapped for an additional charge of $150 each If Sergio spends at least $70 he will receive free shipping on his order Write and solve an inequality to determine how much Sergio needs to spend on each gift in order to receive free shipping
Let g be the cost of one gift
Write an inequality to represent the situation ( g + ) ge 70
Use the Distributive Property g + ge 70
Subtraction Property of Inequality g + 12 - ge 70 -
Simplify 8g ge
Division Property of Inequality 8g _
ge 58 _
Simplify g ge
Check your answer
Since g ge 725 check a larger number 8(8 + 150) ge 70
Sergio must spend at least on each gift ge 70
Reflect
3 Discussion Why is the first step in solving the inequality to use the Distributive Property instead of working inside the parentheses
Your Turn
4 Zachary is planning to send a video game to each of his two brothers If he buys the same game for both brothers and pays $475 to ship each game how much can he spend on each game without spending more than $100 Write and solve an inequality for this situation
Solve each inequality
5 4 _ 3 (6x + 9) lt 4 6 -2 ( 1 _ 4 x + 2 ) ge 5
Module 2 75 Lesson 4
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Explain 2 Creating and Solving Inequalities with Variables on Both Sides
Some inequalities have variable terms on both sides of the inequality symbol You can solve these inequalities the same way you solved equations with variables on both sides Use the properties of inequality to collect all the variable terms on one side and all the constant terms on the other side
Example 2
A The Daily Info charges a fee of $650 plus $80 per week to run an ad The Peoplersquos Paper charges $145 per week For how many weeks must an ad run for the total cost at the Daily Info to be less expensive than the cost at the Peoplersquos Paper Let w be the number of weeks the ad runs in the paper
Write an inequality to represent the situation 650 + 80w lt 145w
Subtraction Property of Inequality 650 + 80w - 80w lt 145w - 80w
Simplify 650 lt 65w
Division Property of Inequality 650 _ 65 lt 65w _ 65
Simplify 10 lt w
The total cost at the Daily Info is less than the cost at the Peoplersquos Paper if the ad runs for more than 10 weeks
B The Home Cleaning Company charges $312 to power-wash the siding of a house plus $12 for each window Power Clean charges $36 per window and the price includes power-washing the siding How many windows must a house have to make the total cost from The Home Cleaning Company less expensive than Power Clean Let w be the number of windows
Write an inequality to represent the situation +12w lt 36w
Subtraction Property of Inequality 312 + 12w - lt 36w -
Simplify 312 lt
Division Property of Inequality 312 _ lt 24w _
Simplify lt w
A house must have more than 13 windows for The Home Cleaning Company to be less expensive than Power Clean
Reflect
7 How would the final inequality change if you divided by ndash24 in the next to last step
Your Turn
8 The school band will sell pizzas to raise money for new uniforms The supplier charges $100 plus $4 per pizza The band members sell the pizzas for $7 each Write and solve an inequality to find how many pizzas the band members will have to sell to make a profit
Module 2 76 Lesson 4
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Elaborate
9 Which inequality symbol would you use to represent the following words or phrases Can you come up with more examples
a at most b farther than c younger than d up to
10 Discussion How are the steps to solving an inequality similar to those for solving an equation How are they different
11 Essential Question Check-In How can you write an inequality that represents a real-world situation
Write an inequality that represents the description and then solve
1 Max has more than 5 carrots (number of carrots Max has = c)
2 Brigitte is shorter than 5 feet (Brigittersquos height = h)
3 Twice a number (x) is less than 10 4 Six more than five times a number (x) is at least twenty-one
5 Dave has $15 to spend on an $8 book and two birthday cards (c) for his friends How much can he spend on each card if he buys the same card for each friend
6 Toni can carry up to 18 lb in her backpack Her lunch weighs 1 lb her gym clothes weigh 2 lb and her books (b) weigh 3 lb each How many books can she carry in her backpack
Evaluate Homework and Practice
bull Online Homeworkbull Hints and Helpbull Extra Practice
Module 2 77 Lesson 4
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Solve each inequality
7 3 (x - 2) gt -3 8 5 + 5 (x + 4) le 20 9 3 + 1 _ 2 (3 - x) lt -7
10 3 (x + 6) - 2 (x + 2) ge 10 11 5 (3 - x) -4 (2 - 3x) gt 2 12 1 _ 2 (4x - 2) - 2 _ 3 (6x + 9) le 4
13 x + 1 gt -5 (7 - 2x) 14 5 _ 3 (6x + 3) le 2x - 7
15 2x le - 2 __ 3 (4x + 4) 16 1 __ 2 (-2x - 10) gt 3 (4 - 6x)
17 -5 - 3x ge 2 (10 + 2x) + 3 18 -3 (9x + 20) ge 15x - 20
19 8 ( 1 _ 4 x - 3) + 24 lt 4 ( x + 5 ) 20 6x - 2 (x + 2) gt 2 - 3 (x + 3)
Module 2 78 Lesson 4
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21 Physics A crane cable can support a maximum load of 15000 kg If a bucket has a mass of 2000 kg and gravel has a mass of 1500 kg for every cubic meter how many cubic meters of gravel (g) can be safely lifted by the crane
22 Find the solution set of each inequality below and then determine which inequalities have the same solution set as 1 _ 3 ( -5x - 3 ) lt 14
a 1 _ 3 (5x + 3) gt -14 b 2 _ 5 (10x + 20) gt 44
c - 2 _ 5 (10x + 20) lt -44 d - 1 _ 3 (5x + 3) lt 14
e 2 _ 5 (10x - 20) gt -44 f 1 _ 3 (5x + 3) lt -14
HOT Focus on Higher Order Thinking
23 Explain the Error Sven is trying to find the maximum amount of time he can spend practicing the five scales of piano music he is supposed to be working on He has 60 minutes to practice piano and would like to spend at least 35 minutes playing songs instead of practicing scales So Sven sets up the following inequality where t is the number of minutes he spends on each scale and solves it
60 - 5t le 35-5t le -25
t ge 5
Sven has concluded that he should spend 5 minutes or more on each scale Is this correct If not what mistake did he make Then solve for the correct answer
Module 2 79 Lesson 4
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24 Critical Thinking Anika wants to determine the maximum number of tulip bulbs (t) she can purchase if each bulb costs $150 She will also need to purchase separate pots for each bulb at $125 each and a bag of potting soil for $1000 Set up an inequality to determine how many tulip bulbs Anika can purchase without spending more than $2000 and solve it Can Anika buy exactly enough bulbs and pots to spend the full $2000 Explain Can you think of a better inequality to describe the answer
25 Geometry The area of the triangle shown is no more than 10 square inches
a Write an inequality that can be used to find x
b Solve the inequality from part a c What is the maximum height of the triangle
Lesson Performance TaskWhen planning an airplane route the trip planner must be careful to consider the range the aircraft can travel and the availability of airports to stop and refuel
A large commercial jet airplane burns approximately 5 gallons of fuel per mile flown plus about 8500 gallons of fuel per trip to reach cruising altitude With a useable fuel capacity of 50000 gallons (there is additional fuel reserved for emergencies) describe the acceptable distance for which an airline could establish a non-stop flight
For flights originating from Chicago determine which cities could be safely reached by a non-stop flight
City Distance from Chicago (miles)
Bangalore India 8530
Jakarta Indonesia 9810
Johannesburg South Africa 8680
Moscow Russia 4970
Paris France 4130
Perth Australia 10970
Tokyo Japan 6300
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eva O
lesiaShutterstock
(2x - 3) in
4 in
Module 2 80 Lesson 4
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Name Class Date
Resource Locker
Explore Truth Tables and Compound StatementsA compound statement is formed by combining two or more simple statements A compound statement can be true or false A compound statement involving AND is true when both simple statements are true A compound statement involving OR is true when either one simple statement or both are true
A Complete the truth table
P QP
True or FalseQ
True or FalseP AND Q
True or False
A dog is a mammal Red is a color
A dog is a mammal Red is not a color
A dog is a fish Red is a color
A dog is a fish Red is not a color
B P AND Q is true when
C Complete the truth table
P QP
True or FalseQ
True or FalseP OR Q
True or False
1 is an odd number 2 is an even number
1 is an odd number 2 is an odd number
1 is an even number 2 is an even number
1 is an even number 2 is an odd number
D P OR Q is true when
Reflect
1 Give two simple statements P and Q for which P AND Q is false and P OR Q is true
Module 2 81 Lesson 5
25 Creating and Solving Compound Inequalities
Essential Question How can you solve a compound inequality and graph the solution set
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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Explain 1 Solving Compound Inequalities Involving ANDCombining two or more simple inequalities forms a compound inequality The graph of a compound inequality involving AND is the intersection or the overlapping region of the simple inequality graphs
Compound Inequalities AND
Words Algebra Graph
All real numbers greater than 2AND less than 6
x gt 2 AND x lt 62 lt x lt 6
All real numbers greater than or equal to 2 AND less than or equal to 6
x ge 2 AND x le 62 le x le 6
Example 1 Solve each compound inequality and graph the solutions
A 4 le x + 2 le 8
4 le x + 2 AND x + 2 le 8 Write the compound inequality using AND
4 - 2 le x + 2 - 2 x + 2 - 2 le 8 - 2 Subtract 2 from both sides of each simple inequality
2 le x x le 6 Simplify
Graph 2 le x
Graph x le 6
Graph the intersection by finding where the two graphs overlap
B -5 le 2x + 3 lt 9
-5 - le 2x + 3 - lt 9 - Subtract from each part of the inequality
le 2x lt Simplify
-8 _ le 2x _ lt 6 _ Divide each part of the inequality by
le x lt Simplify
Graph -4 le x
Graph x lt 3
Graph the intersection by finding where the two graphs overlap -1 0 1 2 3 4 5-5-4 -3 -2
0 2 4 6 8 10 12-8-6-4 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 82 Lesson 5
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Reflect
2 Discussion Explain why 2 le x le 6 can be considered the short method for writing the AND compound inequality x ge 2 AND x le 6
YourTurn
Solve each compound inequality and graph the solutions
3 -2 lt x - 3 lt 5
4 -10 lt 3x + 2 le 8
Explain 2 Solving Compound Inequalities Involving ORThe graph of a compound inequality involving OR is the union or the combined region of the simple inequality graphs
Compound Inequalities OR
Words Algebra Graph
All real numbers less than 2OR greater than 6
x lt 2 OR x gt 6
All real numbers less than or equal to 2OR greater than or equal to 6
x le 2 OR x ge 6
-1 0 1 2 3 4 5-5-4 -3 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 83 Lesson 5
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Example 2 Solve each compound inequality and graph the solutions
A -4 + x gt 1 OR -4 + x lt -3
-4 + x gt 1 OR -4 + x lt -3 Write the compound inequality using OR
-4 + 4 + x gt 1 + 4 -4 + 4 + x lt -3 + 4 Add 4 to both sides of each simple inequality
x gt 5 x lt 1 Simplify
Graph x gt 5
Graph x lt 1
Graph the union by combining the graphs
B 2x le 6 OR 3x gt 12
2x le 6 OR 3x gt 12 Write the compound inequality using OR
2x _ le 6 _ OR 3x _ gt 12 _ Divide the first simple inequality by
x le OR x gt
Graph x le 3
Graph x gt 4
Graph the union by combining the graphs
Reflect
5 Critical Thinking What kind of compound inequality has no solution
Divide the second simple inequality by
Simplify
0 1 2 3 4 5 6-4 -3 -2 -1
-0 1 2 3 4 5 6-4 -3 -2 -1
Module 2 84 Lesson 5
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Your Turn
Solve each compound inequality and graph the solutions
6 x - 5 ge -2 OR x -5 le -6
7 4x -1 lt 15 OR 8x ge 48
Explain 3 Creating Compound Inequalities From GraphsGiven a number line graph with a solution set graphed you can create a compound inequality to fit the graph
Example 3 Write the compound inequality shown by each graph
A
The shaded portion of the graph is not between two values so the compound inequality involves OR
On the left the graph shows an arrow pointing left from -1 and a solid circle so use le
The inequality is x le -1
On the right the graph shows an arrow pointing right from 7 and a solid circle so use ge
The inequality is x ge 7
The compound inequality is x le -1 OR x ge 7
B
The graph is shaded between the values and so the compound inequality involves AND
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The compound inequality is
-1 0 1 2 3 4 5-5-4 -3 -2
4 5 6 7 8 9 100 1 2 3
2 3 4 5 6 7 8-2 -1 0 1
10 2 3 4 5 6 7 8 9-1
Module 2 85 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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Reflect
8 What is a short method to write the compound inequality x ge 0 AND x lt 6
Your Turn
Write the compound inequality shown by each graph
9
10
Explain 4 Expressing Acceptable Levels with Compound Inequalities
You can express quality-controls levels in real-world problems using compound inequalities
Example 4 Write a compound inequality to represent the indicated quality-control level and graph the solutions
A The recommended pH level for swimming pool water is between 72 and 76 inclusive
Let p be the pH level of swimming pool water
72 is less than or equal to pH level is less than or equal to 76
72 le p le 76
The compound inequality is 72 le p le 76
Graph the solutions
0-10 -8-9 -7-6 -5-4 -3 -2 -1
71 72 73 74 75 76 77 78 79 8070
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 86 Lesson 5
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B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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pany
bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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oug
hton
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Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
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tanisakornA
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Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
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onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
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The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
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15 Community Gym charges a $50 membership fee and a $55 monthly fee Workout Gym charges a $200 membership fee and a $45 monthly fee After how many months will the total amount of money paid to both gyms be the same What will the amount be
16 Tina is saving to buy a notebook computer She has two options The first option is to put $200 away initially and save $10 every month The second option is to put $100 away initially and save $30 every month After how many months would Tina save the same amount using either option How much would she save with either option
Use the table to answer each question
Starting Salary Yearly Salary Increase
Company A $24000 $3000
Company B $30000 $2400
Company C $36000 $2000
17 After how many years are the salaries offered by Company A and Company B the same
18 After how many years are the salaries offered by Company B and Company C the same
19 Paul started work at Company B ten years ago at the salary shown in the table At the same time Sharla started at Company C at the salary shown in the table Who earned more during the last year How much more
20 Georgersquos page contains twice as many typed words as Billrsquos page and Billrsquos page contains 50 fewer words than Charliersquos page If each person can type 60 words per minute after one minute the difference between twice the number of words on Billrsquos page and the number of words on Charliersquos page is 210 How many words did Billrsquos page contain initially Use a table to organize the information
Initial number of words
Total number of words after one minute
Module 2 64 Lesson 2
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21 Geometry Sammie bought just enough fencing to border either a rectangular plot or a square plot as shown The perimeters of the plots are the same How many meters of fencing did she buy
HOT Focus on Higher Order Thinking
22 Justify Reasoning Suppose you want to solve the equation 2a + b = 2a where a and b are nonzero real numbers Describe the solution to this equation Justify your description
23 Multi-step A patio in the shape of a rectangle is fenced on all sides with 134 feet of fencing The patio is 5 feet less wide than it is long
a What information can be used to solve the problem How can you find the information
b Describe how to find the area of the patio What is the area of the patio
24 Explain the Error Kevin and Brittany write an equation to represent the following relationship and both students solve their equation Who found the correct equation and solution Why is the other person incorrect
5 times the difference of a number and 20 is the same as half the sum of 4 more than 4 times a number
Kevin Brittany
5 (x - 20) = 1 _ 2 (4x + 4) 5 (20 + x) = 1 _ 2 (4x + 4)
5x - 100 = 2x + 2 100 - 5x = 2x + 2
3x - 100 = 2 100 - 7x = 2
3x = 102 -7x = -98
x = 34 x = 14
(3x + 2) meters
(x + 2) meters
(x + 2) meters
(x - 1) meters
ℓ feet
(ℓ - 5) feet
Module 2 65 Lesson 2
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25 What If Alexa and Zack are solving the following problem
The number of miles on Car A is 50 miles more than the number of miles on Car B and the number of miles on Car B is 30 miles more than the number of miles on Car C All the cars travel 50 miles in 1 hour After 1 hour twice the number of miles on Car A is 70 miles less than 3 times the number of miles on Car C How many miles were there on Car B initially
Alexa assumes there are m miles on Car B Zack assumes there are m miles on Car C Will Zackrsquos answer be the same as Alexarsquos answer Explain
Lesson Performance Task
Stacy Oliver and Jivesh each plan to put a certain amount of money into their savings accounts that earn simple interest of 6 per year Stacy puts $550 more than Jivesh and Oliver puts in 2 times as much as Jivesh After a year the amount in Stacyrsquos account is 2 times the sum of $212 and the amount in Oliverrsquos account How much does each person initially put into his or her account Who had the most money in his or her account after a year Who had the least Explain
Zackrsquos Table Initial Miles
Miles after One Hour
Alexarsquos Table Initial Miles
Miles after One Hour
Amount in Account Initially Amount in Account after One Year
Module 2 66 Lesson 2
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oug
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Name Class Date
Resource Locker
Explore Rearranging Mathematical FormulasLiteral Equations are equations that contain two or more variables There are many literal equations in the form of math science and engineering formulas These formulas may seem like they can only be solved for the variable that is isolated on one side of the formula By using inverse operations and the properties of equality a formula can be rearranged so any variable in the formula can be isolated It is no different than how equations are solved by using inverse operations and the properties of equality
How can you solve the equation 42 = 6x
A42 _ = 6x _ What is the reason for dividing
Why divide by
= x By rearranging the equation x was isolated and the solution was found
The mathematical formula for the volume of a rectangular prism B = Vh or V = ℓwh is a literal equation V represents volume ℓ represents length w represents width and h represents height Using inverse operations the formula can be rearranged to solve for any one of the variables that might be unknown Like solving for x a formula can be rearranged to isolate a variable
B In the formula V = ℓwh the variable h needs to be isolated
The operation of is used in the formula The inverse
operation should be used
to isolate
C V _____ = ℓwh _____
V _ =
The formula rearranged in this way can easily produce the height of the rectangular prism when the volume length and width are known
Reflect
1 Using the formula for a rectangular prism rewrite the formula to solve for ℓ
ℓw
h
Module 2 67 Lesson 3
23 Solving for a VariableEssential Question How do you rewrite formulas and literal equations
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Photo
grap
hyAurora Ph
otosCorb
is
Explain 1 Rearranging Scientific FormulasUse inverse operations to isolate the unknown variable in a scientific formula
The formula for density is D = m __ V Lead has a very high density of 11340 kg m 3 Plastic foam has a very low density of 75 kg m 3 The formula for density can be rearranged to solve for V volume or m mass
Example 1
A A sinker on a fishing line is made of lead and has a volume of 0000015 m 3 What is the mass of the sinker
The density formula can be rearranged to isolate m the mass The values for volume and density can then be substituted into the formula to find the mass
D = m _ V
DV = ( m _ V ) V DV = m
(11340 kg m 3 ) (0000015 m 3 ) = m
017 kg asymp m
B The design for a life preserver requires 03 kilogram of plastic foam to provide proper buoyancy What is the volume of the plastic foam required
Rearrange the density formula to isolate V
D = m _ V
(D) V = m _ V
DV =
DV _ = m _
V =
Now substitute the given values
V = _
V = m 3
Your Turn
2 For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Determine the altitude in feet when t is -275 ∘F and g is 60 ∘F
Module 2 68 Lesson 3
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Explain 2 Rearranging Literal EquationsUsing inverse operations to rearrange literal equations can be applied to any formula The interest formula I = prt is another example of a literal equation In the formula I represents interest p the principal or the initial amount to which interest will be applied r the rate at which interest will be paid and t is the time in years
Example 2
A Find the number of years used in the calculation of a $1000 loan at an interest rate of 5 with interest totaling $600
Solve the formula for t
I = prt
I _ pr = prt
_ pr
I _ pr = t
Substitute the given values Since the interest rate is 5 r = 005$600 __
$1000 middot 005 = t
12 = t
So the length of time for the loan is 12 years
B Determine the interest rate for a $2000 loan that will be paid off in 4 years with interest totaling $640 In order to find the interest rate solve the formula for r
I = prt
I _ = prt _
_ = r
Now substitute the values and simplify
__
( ) ( ) = r
008 = r
So the interest rate is per year
Your Turn
3 The formula y = mx + b is the slope-intercept form of the equation of a line Solve the equation for m
Module 2 69 Lesson 3
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oug
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bull Online Homeworkbull Hints and Helpbull Extra Practice
Solve for the indicated variable in each mathematical formula
1 C = 2πr for r 2 A = 1 __ 2 bh for b 3 y = mx + b for x
4 A = 1 __ 2 (a + b)h for h 5 V = πr2h for h 6 SA = 2πr2 + 2πrh for h
Solve for the indicated variable in each scientific formula
7 d = rt for t 8 PV = nRT for T
9 A = FV - OV _______ T for OV 10 C = Wtc _ 1000 for W
Evaluate Homework and Practice
Elaborate
4 Discussion What could be a reason for isolating a variable in a literal equation
5 Describe a situation in which a formula could be used more easily if it were rearranged Include the formula in your description
6 Essential Question Check-In How do you isolate a variable
Module 2 70 Lesson 3
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cean
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orb
is
Solve for the indicated variable in each literal equation
11 2p + 5r = q for p 12 -10 = xy + z for x 13 a __ b = c for b
14 h - 4 _ j = k for j 15 x __ 5 - g = a for x 16 5p + 9c = p for c
17 2 __ 5 (z + 1) = y for z 18 g (h + 2 __ 3 ) = 1 for h 19 a(n - 3) + 8 = bn for n
20 Which is a possible way to rewrite the equation y = 3x + 3b to solve for b
A b = y - 3x
_ 3 C b = y - 3
_____ 3x
B b = 3(y - 3x) D b = x(y - 3)
21 Sports To find a baseball pitcherrsquos earned run average (ERA) you can use the formula Ei = 9r in which E represents ERA i represents the number of innings pitched and r represents the number of earned runs allowed Solve the equation for E What is a pitcherrsquos ERA if he allows 5 earned runs in 18 innings pitched
22 Meteorology For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Solve the equation for a If the atmospheric temperature is -655 ∘F and the ground temperature is 57 ∘F what is the altitude
Module 2 71 Lesson 3
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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arcourt Publishin
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Rand
y D
uch
aineA
lamy
HOT Focus on Higher Order Thinking
23 Explain the Error A student was asked to use the formula for the perimeter of a rectangle P = 2ℓ + 2w to solve for ℓ The student came up with an answer P - 2w = 2ℓ What error did the student make Explain Then solve for ℓ
24 Multi-Step The formula c = 5p + 215 relates c the total cost in dollars of hosting a birthday party at a skating rink to p the number of people attending If Alliersquos parents are willing to spend $300 for a party how many people can attend
25 Multi-Step The formula for the area of a triangle is A = 1 __ 2 bh in which b represents the length of thebase and h represents the height If a triangle has an area of 192 mm2 and the height is 12 mm what is the measure of the base
Lesson Performance TaskThe following table shows the average low temperatures in Fahrenheit for the city of Boston for several months during the year The formula F = 9 __ 5 C + 32 allows you to determine the temperature in Fahrenheit when given the temperature in Celsius
MonthTemperature in
FahrenheitTemperature in
Celsius
January 22deg
April 41deg
July 65deg
October 47deg
December 28deg
a Use the information given to determine the average low temperatures in Celsius
b Would it ever be possible for the temperature in Celsius to have a greater value than the temperature in Fahrenheit Explain why or why not
Module 2 72 Lesson 3
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
Name Class Date
Resource Locker
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oug
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Mif
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Har
cour
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Com
pan
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mag
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edit
s copy
Patr
ick
Lan
eSo
mos
Imag
esC
orb
is
Explore Creating Inequalities from Verbal DescriptionsAn inequality is a statement that compares two expressions that are not strictly equal by using one of the following inequality signs
Symbol Meaning
lt is less than
le is less than or equal to
gt is greater than
ge is greater than or equal to
ne is not equal to
You have probably seen a sign at an amusement park saying something like ldquoYou must be at least 48 inches tall to ride this riderdquo This statement could be written as h ge 48 in where h represents the height of a person allowed to ride
Nora is planning a birthday party for her little sister Colleen Norarsquos budget will allow her to spend no more than $50 for party supplies Eight children including Colleen will attend the party and Nora wants to determine how much she could spend on party favors for each child She will also purchase a cake for $10 Write an inequality that represents the situation and find possible solutions
A First let c represent the cost of a party favor for each child Write an expression for the total cost of the party as a function of c
c +
B Which inequality symbol should be used to represent the phrase ldquono more thanrdquo
C Write the inequality that represents Norarsquos budget goal
8c + 10 le
D Suppose Nora finds party favors that cost $4 each Use a value of 4 for c and check to see if this inequality is true
8 middot 4 + 10 le 50
le 50
Module 2 73 Lesson 4
24 Creating and Solving Inequalities
Essential Question How do you write and solve an inequality that represents a real-world situation
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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Is the inequality true
Could Nora buy $6 party favors for all of her guests without going over budget
Reflect
1 Why does an inequality represent Norarsquos budget calculation better than an equation
2 The solution set of an inequality consists of all values that make the statement true Describe the whole dollar amounts that are in the solution set for this situation
Explain 1 Creating and Solving Inequalities Involving the Distributive Property
You may need to use the Distributive Property before you can solve an inequality
Distributive Property If a b and c are real numbers then a(b + c) = ab + ac
The inequality sign must be reversed when multiplying or dividing both sides of an inequality by a negative number
Example 1
A Trina is buying 12 shirts for the drama club She will choose a style for the blank shirts and then pay an additional charge of $275 for each shirt to have the club logo If Trina cannot spend more than $99 how much can she spend on each blank shirt Write and solve an inequality to find the possible cost of each blank shirt
Let s represent the cost of each blank shirt
Write an inequality to represent the situation 12(s + 275) le 99
Use the Distributive Property 12s + 33 le 99
Subtraction Property of Inequality 12s + 33 - 33 le 99 - 33
Simplify 12s le 66
Division Property of Inequality 12s ___ 12 le 66 __ 12
Simplify s le 55
Module 2 74 Lesson 4
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cour
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pan
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Check your answer
Since s le 55 check a smaller number 12(5 + 275) le 99
Trina can order blank shirts that cost $550 or less 93 le 99 true
B Sergio needs to buy gifts for 8 friends He wants to give the same gift to all his friends and he plans to have the gifts wrapped for an additional charge of $150 each If Sergio spends at least $70 he will receive free shipping on his order Write and solve an inequality to determine how much Sergio needs to spend on each gift in order to receive free shipping
Let g be the cost of one gift
Write an inequality to represent the situation ( g + ) ge 70
Use the Distributive Property g + ge 70
Subtraction Property of Inequality g + 12 - ge 70 -
Simplify 8g ge
Division Property of Inequality 8g _
ge 58 _
Simplify g ge
Check your answer
Since g ge 725 check a larger number 8(8 + 150) ge 70
Sergio must spend at least on each gift ge 70
Reflect
3 Discussion Why is the first step in solving the inequality to use the Distributive Property instead of working inside the parentheses
Your Turn
4 Zachary is planning to send a video game to each of his two brothers If he buys the same game for both brothers and pays $475 to ship each game how much can he spend on each game without spending more than $100 Write and solve an inequality for this situation
Solve each inequality
5 4 _ 3 (6x + 9) lt 4 6 -2 ( 1 _ 4 x + 2 ) ge 5
Module 2 75 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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Explain 2 Creating and Solving Inequalities with Variables on Both Sides
Some inequalities have variable terms on both sides of the inequality symbol You can solve these inequalities the same way you solved equations with variables on both sides Use the properties of inequality to collect all the variable terms on one side and all the constant terms on the other side
Example 2
A The Daily Info charges a fee of $650 plus $80 per week to run an ad The Peoplersquos Paper charges $145 per week For how many weeks must an ad run for the total cost at the Daily Info to be less expensive than the cost at the Peoplersquos Paper Let w be the number of weeks the ad runs in the paper
Write an inequality to represent the situation 650 + 80w lt 145w
Subtraction Property of Inequality 650 + 80w - 80w lt 145w - 80w
Simplify 650 lt 65w
Division Property of Inequality 650 _ 65 lt 65w _ 65
Simplify 10 lt w
The total cost at the Daily Info is less than the cost at the Peoplersquos Paper if the ad runs for more than 10 weeks
B The Home Cleaning Company charges $312 to power-wash the siding of a house plus $12 for each window Power Clean charges $36 per window and the price includes power-washing the siding How many windows must a house have to make the total cost from The Home Cleaning Company less expensive than Power Clean Let w be the number of windows
Write an inequality to represent the situation +12w lt 36w
Subtraction Property of Inequality 312 + 12w - lt 36w -
Simplify 312 lt
Division Property of Inequality 312 _ lt 24w _
Simplify lt w
A house must have more than 13 windows for The Home Cleaning Company to be less expensive than Power Clean
Reflect
7 How would the final inequality change if you divided by ndash24 in the next to last step
Your Turn
8 The school band will sell pizzas to raise money for new uniforms The supplier charges $100 plus $4 per pizza The band members sell the pizzas for $7 each Write and solve an inequality to find how many pizzas the band members will have to sell to make a profit
Module 2 76 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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oug
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Elaborate
9 Which inequality symbol would you use to represent the following words or phrases Can you come up with more examples
a at most b farther than c younger than d up to
10 Discussion How are the steps to solving an inequality similar to those for solving an equation How are they different
11 Essential Question Check-In How can you write an inequality that represents a real-world situation
Write an inequality that represents the description and then solve
1 Max has more than 5 carrots (number of carrots Max has = c)
2 Brigitte is shorter than 5 feet (Brigittersquos height = h)
3 Twice a number (x) is less than 10 4 Six more than five times a number (x) is at least twenty-one
5 Dave has $15 to spend on an $8 book and two birthday cards (c) for his friends How much can he spend on each card if he buys the same card for each friend
6 Toni can carry up to 18 lb in her backpack Her lunch weighs 1 lb her gym clothes weigh 2 lb and her books (b) weigh 3 lb each How many books can she carry in her backpack
Evaluate Homework and Practice
bull Online Homeworkbull Hints and Helpbull Extra Practice
Module 2 77 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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oug
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arcourt Publishin
g Com
pany
Solve each inequality
7 3 (x - 2) gt -3 8 5 + 5 (x + 4) le 20 9 3 + 1 _ 2 (3 - x) lt -7
10 3 (x + 6) - 2 (x + 2) ge 10 11 5 (3 - x) -4 (2 - 3x) gt 2 12 1 _ 2 (4x - 2) - 2 _ 3 (6x + 9) le 4
13 x + 1 gt -5 (7 - 2x) 14 5 _ 3 (6x + 3) le 2x - 7
15 2x le - 2 __ 3 (4x + 4) 16 1 __ 2 (-2x - 10) gt 3 (4 - 6x)
17 -5 - 3x ge 2 (10 + 2x) + 3 18 -3 (9x + 20) ge 15x - 20
19 8 ( 1 _ 4 x - 3) + 24 lt 4 ( x + 5 ) 20 6x - 2 (x + 2) gt 2 - 3 (x + 3)
Module 2 78 Lesson 4
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oug
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pan
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21 Physics A crane cable can support a maximum load of 15000 kg If a bucket has a mass of 2000 kg and gravel has a mass of 1500 kg for every cubic meter how many cubic meters of gravel (g) can be safely lifted by the crane
22 Find the solution set of each inequality below and then determine which inequalities have the same solution set as 1 _ 3 ( -5x - 3 ) lt 14
a 1 _ 3 (5x + 3) gt -14 b 2 _ 5 (10x + 20) gt 44
c - 2 _ 5 (10x + 20) lt -44 d - 1 _ 3 (5x + 3) lt 14
e 2 _ 5 (10x - 20) gt -44 f 1 _ 3 (5x + 3) lt -14
HOT Focus on Higher Order Thinking
23 Explain the Error Sven is trying to find the maximum amount of time he can spend practicing the five scales of piano music he is supposed to be working on He has 60 minutes to practice piano and would like to spend at least 35 minutes playing songs instead of practicing scales So Sven sets up the following inequality where t is the number of minutes he spends on each scale and solves it
60 - 5t le 35-5t le -25
t ge 5
Sven has concluded that he should spend 5 minutes or more on each scale Is this correct If not what mistake did he make Then solve for the correct answer
Module 2 79 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
24 Critical Thinking Anika wants to determine the maximum number of tulip bulbs (t) she can purchase if each bulb costs $150 She will also need to purchase separate pots for each bulb at $125 each and a bag of potting soil for $1000 Set up an inequality to determine how many tulip bulbs Anika can purchase without spending more than $2000 and solve it Can Anika buy exactly enough bulbs and pots to spend the full $2000 Explain Can you think of a better inequality to describe the answer
25 Geometry The area of the triangle shown is no more than 10 square inches
a Write an inequality that can be used to find x
b Solve the inequality from part a c What is the maximum height of the triangle
Lesson Performance TaskWhen planning an airplane route the trip planner must be careful to consider the range the aircraft can travel and the availability of airports to stop and refuel
A large commercial jet airplane burns approximately 5 gallons of fuel per mile flown plus about 8500 gallons of fuel per trip to reach cruising altitude With a useable fuel capacity of 50000 gallons (there is additional fuel reserved for emergencies) describe the acceptable distance for which an airline could establish a non-stop flight
For flights originating from Chicago determine which cities could be safely reached by a non-stop flight
City Distance from Chicago (miles)
Bangalore India 8530
Jakarta Indonesia 9810
Johannesburg South Africa 8680
Moscow Russia 4970
Paris France 4130
Perth Australia 10970
Tokyo Japan 6300
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(2x - 3) in
4 in
Module 2 80 Lesson 4
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Name Class Date
Resource Locker
Explore Truth Tables and Compound StatementsA compound statement is formed by combining two or more simple statements A compound statement can be true or false A compound statement involving AND is true when both simple statements are true A compound statement involving OR is true when either one simple statement or both are true
A Complete the truth table
P QP
True or FalseQ
True or FalseP AND Q
True or False
A dog is a mammal Red is a color
A dog is a mammal Red is not a color
A dog is a fish Red is a color
A dog is a fish Red is not a color
B P AND Q is true when
C Complete the truth table
P QP
True or FalseQ
True or FalseP OR Q
True or False
1 is an odd number 2 is an even number
1 is an odd number 2 is an odd number
1 is an even number 2 is an even number
1 is an even number 2 is an odd number
D P OR Q is true when
Reflect
1 Give two simple statements P and Q for which P AND Q is false and P OR Q is true
Module 2 81 Lesson 5
25 Creating and Solving Compound Inequalities
Essential Question How can you solve a compound inequality and graph the solution set
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Explain 1 Solving Compound Inequalities Involving ANDCombining two or more simple inequalities forms a compound inequality The graph of a compound inequality involving AND is the intersection or the overlapping region of the simple inequality graphs
Compound Inequalities AND
Words Algebra Graph
All real numbers greater than 2AND less than 6
x gt 2 AND x lt 62 lt x lt 6
All real numbers greater than or equal to 2 AND less than or equal to 6
x ge 2 AND x le 62 le x le 6
Example 1 Solve each compound inequality and graph the solutions
A 4 le x + 2 le 8
4 le x + 2 AND x + 2 le 8 Write the compound inequality using AND
4 - 2 le x + 2 - 2 x + 2 - 2 le 8 - 2 Subtract 2 from both sides of each simple inequality
2 le x x le 6 Simplify
Graph 2 le x
Graph x le 6
Graph the intersection by finding where the two graphs overlap
B -5 le 2x + 3 lt 9
-5 - le 2x + 3 - lt 9 - Subtract from each part of the inequality
le 2x lt Simplify
-8 _ le 2x _ lt 6 _ Divide each part of the inequality by
le x lt Simplify
Graph -4 le x
Graph x lt 3
Graph the intersection by finding where the two graphs overlap -1 0 1 2 3 4 5-5-4 -3 -2
0 2 4 6 8 10 12-8-6-4 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 82 Lesson 5
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Reflect
2 Discussion Explain why 2 le x le 6 can be considered the short method for writing the AND compound inequality x ge 2 AND x le 6
YourTurn
Solve each compound inequality and graph the solutions
3 -2 lt x - 3 lt 5
4 -10 lt 3x + 2 le 8
Explain 2 Solving Compound Inequalities Involving ORThe graph of a compound inequality involving OR is the union or the combined region of the simple inequality graphs
Compound Inequalities OR
Words Algebra Graph
All real numbers less than 2OR greater than 6
x lt 2 OR x gt 6
All real numbers less than or equal to 2OR greater than or equal to 6
x le 2 OR x ge 6
-1 0 1 2 3 4 5-5-4 -3 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 83 Lesson 5
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Example 2 Solve each compound inequality and graph the solutions
A -4 + x gt 1 OR -4 + x lt -3
-4 + x gt 1 OR -4 + x lt -3 Write the compound inequality using OR
-4 + 4 + x gt 1 + 4 -4 + 4 + x lt -3 + 4 Add 4 to both sides of each simple inequality
x gt 5 x lt 1 Simplify
Graph x gt 5
Graph x lt 1
Graph the union by combining the graphs
B 2x le 6 OR 3x gt 12
2x le 6 OR 3x gt 12 Write the compound inequality using OR
2x _ le 6 _ OR 3x _ gt 12 _ Divide the first simple inequality by
x le OR x gt
Graph x le 3
Graph x gt 4
Graph the union by combining the graphs
Reflect
5 Critical Thinking What kind of compound inequality has no solution
Divide the second simple inequality by
Simplify
0 1 2 3 4 5 6-4 -3 -2 -1
-0 1 2 3 4 5 6-4 -3 -2 -1
Module 2 84 Lesson 5
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Your Turn
Solve each compound inequality and graph the solutions
6 x - 5 ge -2 OR x -5 le -6
7 4x -1 lt 15 OR 8x ge 48
Explain 3 Creating Compound Inequalities From GraphsGiven a number line graph with a solution set graphed you can create a compound inequality to fit the graph
Example 3 Write the compound inequality shown by each graph
A
The shaded portion of the graph is not between two values so the compound inequality involves OR
On the left the graph shows an arrow pointing left from -1 and a solid circle so use le
The inequality is x le -1
On the right the graph shows an arrow pointing right from 7 and a solid circle so use ge
The inequality is x ge 7
The compound inequality is x le -1 OR x ge 7
B
The graph is shaded between the values and so the compound inequality involves AND
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The compound inequality is
-1 0 1 2 3 4 5-5-4 -3 -2
4 5 6 7 8 9 100 1 2 3
2 3 4 5 6 7 8-2 -1 0 1
10 2 3 4 5 6 7 8 9-1
Module 2 85 Lesson 5
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oug
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Reflect
8 What is a short method to write the compound inequality x ge 0 AND x lt 6
Your Turn
Write the compound inequality shown by each graph
9
10
Explain 4 Expressing Acceptable Levels with Compound Inequalities
You can express quality-controls levels in real-world problems using compound inequalities
Example 4 Write a compound inequality to represent the indicated quality-control level and graph the solutions
A The recommended pH level for swimming pool water is between 72 and 76 inclusive
Let p be the pH level of swimming pool water
72 is less than or equal to pH level is less than or equal to 76
72 le p le 76
The compound inequality is 72 le p le 76
Graph the solutions
0-10 -8-9 -7-6 -5-4 -3 -2 -1
71 72 73 74 75 76 77 78 79 8070
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 86 Lesson 5
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oug
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B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
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oug
hton Mifflin H
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pany
bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
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oug
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Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
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oug
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Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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bik
erid
erlo
nd
onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
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oug
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cour
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21 Geometry Sammie bought just enough fencing to border either a rectangular plot or a square plot as shown The perimeters of the plots are the same How many meters of fencing did she buy
HOT Focus on Higher Order Thinking
22 Justify Reasoning Suppose you want to solve the equation 2a + b = 2a where a and b are nonzero real numbers Describe the solution to this equation Justify your description
23 Multi-step A patio in the shape of a rectangle is fenced on all sides with 134 feet of fencing The patio is 5 feet less wide than it is long
a What information can be used to solve the problem How can you find the information
b Describe how to find the area of the patio What is the area of the patio
24 Explain the Error Kevin and Brittany write an equation to represent the following relationship and both students solve their equation Who found the correct equation and solution Why is the other person incorrect
5 times the difference of a number and 20 is the same as half the sum of 4 more than 4 times a number
Kevin Brittany
5 (x - 20) = 1 _ 2 (4x + 4) 5 (20 + x) = 1 _ 2 (4x + 4)
5x - 100 = 2x + 2 100 - 5x = 2x + 2
3x - 100 = 2 100 - 7x = 2
3x = 102 -7x = -98
x = 34 x = 14
(3x + 2) meters
(x + 2) meters
(x + 2) meters
(x - 1) meters
ℓ feet
(ℓ - 5) feet
Module 2 65 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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25 What If Alexa and Zack are solving the following problem
The number of miles on Car A is 50 miles more than the number of miles on Car B and the number of miles on Car B is 30 miles more than the number of miles on Car C All the cars travel 50 miles in 1 hour After 1 hour twice the number of miles on Car A is 70 miles less than 3 times the number of miles on Car C How many miles were there on Car B initially
Alexa assumes there are m miles on Car B Zack assumes there are m miles on Car C Will Zackrsquos answer be the same as Alexarsquos answer Explain
Lesson Performance Task
Stacy Oliver and Jivesh each plan to put a certain amount of money into their savings accounts that earn simple interest of 6 per year Stacy puts $550 more than Jivesh and Oliver puts in 2 times as much as Jivesh After a year the amount in Stacyrsquos account is 2 times the sum of $212 and the amount in Oliverrsquos account How much does each person initially put into his or her account Who had the most money in his or her account after a year Who had the least Explain
Zackrsquos Table Initial Miles
Miles after One Hour
Alexarsquos Table Initial Miles
Miles after One Hour
Amount in Account Initially Amount in Account after One Year
Module 2 66 Lesson 2
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Name Class Date
Resource Locker
Explore Rearranging Mathematical FormulasLiteral Equations are equations that contain two or more variables There are many literal equations in the form of math science and engineering formulas These formulas may seem like they can only be solved for the variable that is isolated on one side of the formula By using inverse operations and the properties of equality a formula can be rearranged so any variable in the formula can be isolated It is no different than how equations are solved by using inverse operations and the properties of equality
How can you solve the equation 42 = 6x
A42 _ = 6x _ What is the reason for dividing
Why divide by
= x By rearranging the equation x was isolated and the solution was found
The mathematical formula for the volume of a rectangular prism B = Vh or V = ℓwh is a literal equation V represents volume ℓ represents length w represents width and h represents height Using inverse operations the formula can be rearranged to solve for any one of the variables that might be unknown Like solving for x a formula can be rearranged to isolate a variable
B In the formula V = ℓwh the variable h needs to be isolated
The operation of is used in the formula The inverse
operation should be used
to isolate
C V _____ = ℓwh _____
V _ =
The formula rearranged in this way can easily produce the height of the rectangular prism when the volume length and width are known
Reflect
1 Using the formula for a rectangular prism rewrite the formula to solve for ℓ
ℓw
h
Module 2 67 Lesson 3
23 Solving for a VariableEssential Question How do you rewrite formulas and literal equations
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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hyAurora Ph
otosCorb
is
Explain 1 Rearranging Scientific FormulasUse inverse operations to isolate the unknown variable in a scientific formula
The formula for density is D = m __ V Lead has a very high density of 11340 kg m 3 Plastic foam has a very low density of 75 kg m 3 The formula for density can be rearranged to solve for V volume or m mass
Example 1
A A sinker on a fishing line is made of lead and has a volume of 0000015 m 3 What is the mass of the sinker
The density formula can be rearranged to isolate m the mass The values for volume and density can then be substituted into the formula to find the mass
D = m _ V
DV = ( m _ V ) V DV = m
(11340 kg m 3 ) (0000015 m 3 ) = m
017 kg asymp m
B The design for a life preserver requires 03 kilogram of plastic foam to provide proper buoyancy What is the volume of the plastic foam required
Rearrange the density formula to isolate V
D = m _ V
(D) V = m _ V
DV =
DV _ = m _
V =
Now substitute the given values
V = _
V = m 3
Your Turn
2 For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Determine the altitude in feet when t is -275 ∘F and g is 60 ∘F
Module 2 68 Lesson 3
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Explain 2 Rearranging Literal EquationsUsing inverse operations to rearrange literal equations can be applied to any formula The interest formula I = prt is another example of a literal equation In the formula I represents interest p the principal or the initial amount to which interest will be applied r the rate at which interest will be paid and t is the time in years
Example 2
A Find the number of years used in the calculation of a $1000 loan at an interest rate of 5 with interest totaling $600
Solve the formula for t
I = prt
I _ pr = prt
_ pr
I _ pr = t
Substitute the given values Since the interest rate is 5 r = 005$600 __
$1000 middot 005 = t
12 = t
So the length of time for the loan is 12 years
B Determine the interest rate for a $2000 loan that will be paid off in 4 years with interest totaling $640 In order to find the interest rate solve the formula for r
I = prt
I _ = prt _
_ = r
Now substitute the values and simplify
__
( ) ( ) = r
008 = r
So the interest rate is per year
Your Turn
3 The formula y = mx + b is the slope-intercept form of the equation of a line Solve the equation for m
Module 2 69 Lesson 3
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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bull Online Homeworkbull Hints and Helpbull Extra Practice
Solve for the indicated variable in each mathematical formula
1 C = 2πr for r 2 A = 1 __ 2 bh for b 3 y = mx + b for x
4 A = 1 __ 2 (a + b)h for h 5 V = πr2h for h 6 SA = 2πr2 + 2πrh for h
Solve for the indicated variable in each scientific formula
7 d = rt for t 8 PV = nRT for T
9 A = FV - OV _______ T for OV 10 C = Wtc _ 1000 for W
Evaluate Homework and Practice
Elaborate
4 Discussion What could be a reason for isolating a variable in a literal equation
5 Describe a situation in which a formula could be used more easily if it were rearranged Include the formula in your description
6 Essential Question Check-In How do you isolate a variable
Module 2 70 Lesson 3
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cean
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orb
is
Solve for the indicated variable in each literal equation
11 2p + 5r = q for p 12 -10 = xy + z for x 13 a __ b = c for b
14 h - 4 _ j = k for j 15 x __ 5 - g = a for x 16 5p + 9c = p for c
17 2 __ 5 (z + 1) = y for z 18 g (h + 2 __ 3 ) = 1 for h 19 a(n - 3) + 8 = bn for n
20 Which is a possible way to rewrite the equation y = 3x + 3b to solve for b
A b = y - 3x
_ 3 C b = y - 3
_____ 3x
B b = 3(y - 3x) D b = x(y - 3)
21 Sports To find a baseball pitcherrsquos earned run average (ERA) you can use the formula Ei = 9r in which E represents ERA i represents the number of innings pitched and r represents the number of earned runs allowed Solve the equation for E What is a pitcherrsquos ERA if he allows 5 earned runs in 18 innings pitched
22 Meteorology For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Solve the equation for a If the atmospheric temperature is -655 ∘F and the ground temperature is 57 ∘F what is the altitude
Module 2 71 Lesson 3
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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Rand
y D
uch
aineA
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HOT Focus on Higher Order Thinking
23 Explain the Error A student was asked to use the formula for the perimeter of a rectangle P = 2ℓ + 2w to solve for ℓ The student came up with an answer P - 2w = 2ℓ What error did the student make Explain Then solve for ℓ
24 Multi-Step The formula c = 5p + 215 relates c the total cost in dollars of hosting a birthday party at a skating rink to p the number of people attending If Alliersquos parents are willing to spend $300 for a party how many people can attend
25 Multi-Step The formula for the area of a triangle is A = 1 __ 2 bh in which b represents the length of thebase and h represents the height If a triangle has an area of 192 mm2 and the height is 12 mm what is the measure of the base
Lesson Performance TaskThe following table shows the average low temperatures in Fahrenheit for the city of Boston for several months during the year The formula F = 9 __ 5 C + 32 allows you to determine the temperature in Fahrenheit when given the temperature in Celsius
MonthTemperature in
FahrenheitTemperature in
Celsius
January 22deg
April 41deg
July 65deg
October 47deg
December 28deg
a Use the information given to determine the average low temperatures in Celsius
b Would it ever be possible for the temperature in Celsius to have a greater value than the temperature in Fahrenheit Explain why or why not
Module 2 72 Lesson 3
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
Name Class Date
Resource Locker
copy H
oug
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Mif
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cour
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Com
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mag
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edit
s copy
Patr
ick
Lan
eSo
mos
Imag
esC
orb
is
Explore Creating Inequalities from Verbal DescriptionsAn inequality is a statement that compares two expressions that are not strictly equal by using one of the following inequality signs
Symbol Meaning
lt is less than
le is less than or equal to
gt is greater than
ge is greater than or equal to
ne is not equal to
You have probably seen a sign at an amusement park saying something like ldquoYou must be at least 48 inches tall to ride this riderdquo This statement could be written as h ge 48 in where h represents the height of a person allowed to ride
Nora is planning a birthday party for her little sister Colleen Norarsquos budget will allow her to spend no more than $50 for party supplies Eight children including Colleen will attend the party and Nora wants to determine how much she could spend on party favors for each child She will also purchase a cake for $10 Write an inequality that represents the situation and find possible solutions
A First let c represent the cost of a party favor for each child Write an expression for the total cost of the party as a function of c
c +
B Which inequality symbol should be used to represent the phrase ldquono more thanrdquo
C Write the inequality that represents Norarsquos budget goal
8c + 10 le
D Suppose Nora finds party favors that cost $4 each Use a value of 4 for c and check to see if this inequality is true
8 middot 4 + 10 le 50
le 50
Module 2 73 Lesson 4
24 Creating and Solving Inequalities
Essential Question How do you write and solve an inequality that represents a real-world situation
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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pany
Is the inequality true
Could Nora buy $6 party favors for all of her guests without going over budget
Reflect
1 Why does an inequality represent Norarsquos budget calculation better than an equation
2 The solution set of an inequality consists of all values that make the statement true Describe the whole dollar amounts that are in the solution set for this situation
Explain 1 Creating and Solving Inequalities Involving the Distributive Property
You may need to use the Distributive Property before you can solve an inequality
Distributive Property If a b and c are real numbers then a(b + c) = ab + ac
The inequality sign must be reversed when multiplying or dividing both sides of an inequality by a negative number
Example 1
A Trina is buying 12 shirts for the drama club She will choose a style for the blank shirts and then pay an additional charge of $275 for each shirt to have the club logo If Trina cannot spend more than $99 how much can she spend on each blank shirt Write and solve an inequality to find the possible cost of each blank shirt
Let s represent the cost of each blank shirt
Write an inequality to represent the situation 12(s + 275) le 99
Use the Distributive Property 12s + 33 le 99
Subtraction Property of Inequality 12s + 33 - 33 le 99 - 33
Simplify 12s le 66
Division Property of Inequality 12s ___ 12 le 66 __ 12
Simplify s le 55
Module 2 74 Lesson 4
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Check your answer
Since s le 55 check a smaller number 12(5 + 275) le 99
Trina can order blank shirts that cost $550 or less 93 le 99 true
B Sergio needs to buy gifts for 8 friends He wants to give the same gift to all his friends and he plans to have the gifts wrapped for an additional charge of $150 each If Sergio spends at least $70 he will receive free shipping on his order Write and solve an inequality to determine how much Sergio needs to spend on each gift in order to receive free shipping
Let g be the cost of one gift
Write an inequality to represent the situation ( g + ) ge 70
Use the Distributive Property g + ge 70
Subtraction Property of Inequality g + 12 - ge 70 -
Simplify 8g ge
Division Property of Inequality 8g _
ge 58 _
Simplify g ge
Check your answer
Since g ge 725 check a larger number 8(8 + 150) ge 70
Sergio must spend at least on each gift ge 70
Reflect
3 Discussion Why is the first step in solving the inequality to use the Distributive Property instead of working inside the parentheses
Your Turn
4 Zachary is planning to send a video game to each of his two brothers If he buys the same game for both brothers and pays $475 to ship each game how much can he spend on each game without spending more than $100 Write and solve an inequality for this situation
Solve each inequality
5 4 _ 3 (6x + 9) lt 4 6 -2 ( 1 _ 4 x + 2 ) ge 5
Module 2 75 Lesson 4
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Explain 2 Creating and Solving Inequalities with Variables on Both Sides
Some inequalities have variable terms on both sides of the inequality symbol You can solve these inequalities the same way you solved equations with variables on both sides Use the properties of inequality to collect all the variable terms on one side and all the constant terms on the other side
Example 2
A The Daily Info charges a fee of $650 plus $80 per week to run an ad The Peoplersquos Paper charges $145 per week For how many weeks must an ad run for the total cost at the Daily Info to be less expensive than the cost at the Peoplersquos Paper Let w be the number of weeks the ad runs in the paper
Write an inequality to represent the situation 650 + 80w lt 145w
Subtraction Property of Inequality 650 + 80w - 80w lt 145w - 80w
Simplify 650 lt 65w
Division Property of Inequality 650 _ 65 lt 65w _ 65
Simplify 10 lt w
The total cost at the Daily Info is less than the cost at the Peoplersquos Paper if the ad runs for more than 10 weeks
B The Home Cleaning Company charges $312 to power-wash the siding of a house plus $12 for each window Power Clean charges $36 per window and the price includes power-washing the siding How many windows must a house have to make the total cost from The Home Cleaning Company less expensive than Power Clean Let w be the number of windows
Write an inequality to represent the situation +12w lt 36w
Subtraction Property of Inequality 312 + 12w - lt 36w -
Simplify 312 lt
Division Property of Inequality 312 _ lt 24w _
Simplify lt w
A house must have more than 13 windows for The Home Cleaning Company to be less expensive than Power Clean
Reflect
7 How would the final inequality change if you divided by ndash24 in the next to last step
Your Turn
8 The school band will sell pizzas to raise money for new uniforms The supplier charges $100 plus $4 per pizza The band members sell the pizzas for $7 each Write and solve an inequality to find how many pizzas the band members will have to sell to make a profit
Module 2 76 Lesson 4
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Elaborate
9 Which inequality symbol would you use to represent the following words or phrases Can you come up with more examples
a at most b farther than c younger than d up to
10 Discussion How are the steps to solving an inequality similar to those for solving an equation How are they different
11 Essential Question Check-In How can you write an inequality that represents a real-world situation
Write an inequality that represents the description and then solve
1 Max has more than 5 carrots (number of carrots Max has = c)
2 Brigitte is shorter than 5 feet (Brigittersquos height = h)
3 Twice a number (x) is less than 10 4 Six more than five times a number (x) is at least twenty-one
5 Dave has $15 to spend on an $8 book and two birthday cards (c) for his friends How much can he spend on each card if he buys the same card for each friend
6 Toni can carry up to 18 lb in her backpack Her lunch weighs 1 lb her gym clothes weigh 2 lb and her books (b) weigh 3 lb each How many books can she carry in her backpack
Evaluate Homework and Practice
bull Online Homeworkbull Hints and Helpbull Extra Practice
Module 2 77 Lesson 4
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pany
Solve each inequality
7 3 (x - 2) gt -3 8 5 + 5 (x + 4) le 20 9 3 + 1 _ 2 (3 - x) lt -7
10 3 (x + 6) - 2 (x + 2) ge 10 11 5 (3 - x) -4 (2 - 3x) gt 2 12 1 _ 2 (4x - 2) - 2 _ 3 (6x + 9) le 4
13 x + 1 gt -5 (7 - 2x) 14 5 _ 3 (6x + 3) le 2x - 7
15 2x le - 2 __ 3 (4x + 4) 16 1 __ 2 (-2x - 10) gt 3 (4 - 6x)
17 -5 - 3x ge 2 (10 + 2x) + 3 18 -3 (9x + 20) ge 15x - 20
19 8 ( 1 _ 4 x - 3) + 24 lt 4 ( x + 5 ) 20 6x - 2 (x + 2) gt 2 - 3 (x + 3)
Module 2 78 Lesson 4
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21 Physics A crane cable can support a maximum load of 15000 kg If a bucket has a mass of 2000 kg and gravel has a mass of 1500 kg for every cubic meter how many cubic meters of gravel (g) can be safely lifted by the crane
22 Find the solution set of each inequality below and then determine which inequalities have the same solution set as 1 _ 3 ( -5x - 3 ) lt 14
a 1 _ 3 (5x + 3) gt -14 b 2 _ 5 (10x + 20) gt 44
c - 2 _ 5 (10x + 20) lt -44 d - 1 _ 3 (5x + 3) lt 14
e 2 _ 5 (10x - 20) gt -44 f 1 _ 3 (5x + 3) lt -14
HOT Focus on Higher Order Thinking
23 Explain the Error Sven is trying to find the maximum amount of time he can spend practicing the five scales of piano music he is supposed to be working on He has 60 minutes to practice piano and would like to spend at least 35 minutes playing songs instead of practicing scales So Sven sets up the following inequality where t is the number of minutes he spends on each scale and solves it
60 - 5t le 35-5t le -25
t ge 5
Sven has concluded that he should spend 5 minutes or more on each scale Is this correct If not what mistake did he make Then solve for the correct answer
Module 2 79 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
24 Critical Thinking Anika wants to determine the maximum number of tulip bulbs (t) she can purchase if each bulb costs $150 She will also need to purchase separate pots for each bulb at $125 each and a bag of potting soil for $1000 Set up an inequality to determine how many tulip bulbs Anika can purchase without spending more than $2000 and solve it Can Anika buy exactly enough bulbs and pots to spend the full $2000 Explain Can you think of a better inequality to describe the answer
25 Geometry The area of the triangle shown is no more than 10 square inches
a Write an inequality that can be used to find x
b Solve the inequality from part a c What is the maximum height of the triangle
Lesson Performance TaskWhen planning an airplane route the trip planner must be careful to consider the range the aircraft can travel and the availability of airports to stop and refuel
A large commercial jet airplane burns approximately 5 gallons of fuel per mile flown plus about 8500 gallons of fuel per trip to reach cruising altitude With a useable fuel capacity of 50000 gallons (there is additional fuel reserved for emergencies) describe the acceptable distance for which an airline could establish a non-stop flight
For flights originating from Chicago determine which cities could be safely reached by a non-stop flight
City Distance from Chicago (miles)
Bangalore India 8530
Jakarta Indonesia 9810
Johannesburg South Africa 8680
Moscow Russia 4970
Paris France 4130
Perth Australia 10970
Tokyo Japan 6300
copy H
oug
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age cred
its copySarych
eva O
lesiaShutterstock
(2x - 3) in
4 in
Module 2 80 Lesson 4
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Name Class Date
Resource Locker
Explore Truth Tables and Compound StatementsA compound statement is formed by combining two or more simple statements A compound statement can be true or false A compound statement involving AND is true when both simple statements are true A compound statement involving OR is true when either one simple statement or both are true
A Complete the truth table
P QP
True or FalseQ
True or FalseP AND Q
True or False
A dog is a mammal Red is a color
A dog is a mammal Red is not a color
A dog is a fish Red is a color
A dog is a fish Red is not a color
B P AND Q is true when
C Complete the truth table
P QP
True or FalseQ
True or FalseP OR Q
True or False
1 is an odd number 2 is an even number
1 is an odd number 2 is an odd number
1 is an even number 2 is an even number
1 is an even number 2 is an odd number
D P OR Q is true when
Reflect
1 Give two simple statements P and Q for which P AND Q is false and P OR Q is true
Module 2 81 Lesson 5
25 Creating and Solving Compound Inequalities
Essential Question How can you solve a compound inequality and graph the solution set
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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Explain 1 Solving Compound Inequalities Involving ANDCombining two or more simple inequalities forms a compound inequality The graph of a compound inequality involving AND is the intersection or the overlapping region of the simple inequality graphs
Compound Inequalities AND
Words Algebra Graph
All real numbers greater than 2AND less than 6
x gt 2 AND x lt 62 lt x lt 6
All real numbers greater than or equal to 2 AND less than or equal to 6
x ge 2 AND x le 62 le x le 6
Example 1 Solve each compound inequality and graph the solutions
A 4 le x + 2 le 8
4 le x + 2 AND x + 2 le 8 Write the compound inequality using AND
4 - 2 le x + 2 - 2 x + 2 - 2 le 8 - 2 Subtract 2 from both sides of each simple inequality
2 le x x le 6 Simplify
Graph 2 le x
Graph x le 6
Graph the intersection by finding where the two graphs overlap
B -5 le 2x + 3 lt 9
-5 - le 2x + 3 - lt 9 - Subtract from each part of the inequality
le 2x lt Simplify
-8 _ le 2x _ lt 6 _ Divide each part of the inequality by
le x lt Simplify
Graph -4 le x
Graph x lt 3
Graph the intersection by finding where the two graphs overlap -1 0 1 2 3 4 5-5-4 -3 -2
0 2 4 6 8 10 12-8-6-4 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 82 Lesson 5
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Reflect
2 Discussion Explain why 2 le x le 6 can be considered the short method for writing the AND compound inequality x ge 2 AND x le 6
YourTurn
Solve each compound inequality and graph the solutions
3 -2 lt x - 3 lt 5
4 -10 lt 3x + 2 le 8
Explain 2 Solving Compound Inequalities Involving ORThe graph of a compound inequality involving OR is the union or the combined region of the simple inequality graphs
Compound Inequalities OR
Words Algebra Graph
All real numbers less than 2OR greater than 6
x lt 2 OR x gt 6
All real numbers less than or equal to 2OR greater than or equal to 6
x le 2 OR x ge 6
-1 0 1 2 3 4 5-5-4 -3 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 83 Lesson 5
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oug
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Example 2 Solve each compound inequality and graph the solutions
A -4 + x gt 1 OR -4 + x lt -3
-4 + x gt 1 OR -4 + x lt -3 Write the compound inequality using OR
-4 + 4 + x gt 1 + 4 -4 + 4 + x lt -3 + 4 Add 4 to both sides of each simple inequality
x gt 5 x lt 1 Simplify
Graph x gt 5
Graph x lt 1
Graph the union by combining the graphs
B 2x le 6 OR 3x gt 12
2x le 6 OR 3x gt 12 Write the compound inequality using OR
2x _ le 6 _ OR 3x _ gt 12 _ Divide the first simple inequality by
x le OR x gt
Graph x le 3
Graph x gt 4
Graph the union by combining the graphs
Reflect
5 Critical Thinking What kind of compound inequality has no solution
Divide the second simple inequality by
Simplify
0 1 2 3 4 5 6-4 -3 -2 -1
-0 1 2 3 4 5 6-4 -3 -2 -1
Module 2 84 Lesson 5
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Your Turn
Solve each compound inequality and graph the solutions
6 x - 5 ge -2 OR x -5 le -6
7 4x -1 lt 15 OR 8x ge 48
Explain 3 Creating Compound Inequalities From GraphsGiven a number line graph with a solution set graphed you can create a compound inequality to fit the graph
Example 3 Write the compound inequality shown by each graph
A
The shaded portion of the graph is not between two values so the compound inequality involves OR
On the left the graph shows an arrow pointing left from -1 and a solid circle so use le
The inequality is x le -1
On the right the graph shows an arrow pointing right from 7 and a solid circle so use ge
The inequality is x ge 7
The compound inequality is x le -1 OR x ge 7
B
The graph is shaded between the values and so the compound inequality involves AND
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The compound inequality is
-1 0 1 2 3 4 5-5-4 -3 -2
4 5 6 7 8 9 100 1 2 3
2 3 4 5 6 7 8-2 -1 0 1
10 2 3 4 5 6 7 8 9-1
Module 2 85 Lesson 5
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oug
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pany
Reflect
8 What is a short method to write the compound inequality x ge 0 AND x lt 6
Your Turn
Write the compound inequality shown by each graph
9
10
Explain 4 Expressing Acceptable Levels with Compound Inequalities
You can express quality-controls levels in real-world problems using compound inequalities
Example 4 Write a compound inequality to represent the indicated quality-control level and graph the solutions
A The recommended pH level for swimming pool water is between 72 and 76 inclusive
Let p be the pH level of swimming pool water
72 is less than or equal to pH level is less than or equal to 76
72 le p le 76
The compound inequality is 72 le p le 76
Graph the solutions
0-10 -8-9 -7-6 -5-4 -3 -2 -1
71 72 73 74 75 76 77 78 79 8070
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 86 Lesson 5
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B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
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oug
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pany
bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
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Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
arcourt Publishin
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pany bull Im
age C
redits copy
Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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Mif
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Har
cour
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lishi
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Com
pan
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mag
e C
red
its
copy
bik
erid
erlo
nd
onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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pany
The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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pany
25 What If Alexa and Zack are solving the following problem
The number of miles on Car A is 50 miles more than the number of miles on Car B and the number of miles on Car B is 30 miles more than the number of miles on Car C All the cars travel 50 miles in 1 hour After 1 hour twice the number of miles on Car A is 70 miles less than 3 times the number of miles on Car C How many miles were there on Car B initially
Alexa assumes there are m miles on Car B Zack assumes there are m miles on Car C Will Zackrsquos answer be the same as Alexarsquos answer Explain
Lesson Performance Task
Stacy Oliver and Jivesh each plan to put a certain amount of money into their savings accounts that earn simple interest of 6 per year Stacy puts $550 more than Jivesh and Oliver puts in 2 times as much as Jivesh After a year the amount in Stacyrsquos account is 2 times the sum of $212 and the amount in Oliverrsquos account How much does each person initially put into his or her account Who had the most money in his or her account after a year Who had the least Explain
Zackrsquos Table Initial Miles
Miles after One Hour
Alexarsquos Table Initial Miles
Miles after One Hour
Amount in Account Initially Amount in Account after One Year
Module 2 66 Lesson 2
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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pan
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Name Class Date
Resource Locker
Explore Rearranging Mathematical FormulasLiteral Equations are equations that contain two or more variables There are many literal equations in the form of math science and engineering formulas These formulas may seem like they can only be solved for the variable that is isolated on one side of the formula By using inverse operations and the properties of equality a formula can be rearranged so any variable in the formula can be isolated It is no different than how equations are solved by using inverse operations and the properties of equality
How can you solve the equation 42 = 6x
A42 _ = 6x _ What is the reason for dividing
Why divide by
= x By rearranging the equation x was isolated and the solution was found
The mathematical formula for the volume of a rectangular prism B = Vh or V = ℓwh is a literal equation V represents volume ℓ represents length w represents width and h represents height Using inverse operations the formula can be rearranged to solve for any one of the variables that might be unknown Like solving for x a formula can be rearranged to isolate a variable
B In the formula V = ℓwh the variable h needs to be isolated
The operation of is used in the formula The inverse
operation should be used
to isolate
C V _____ = ℓwh _____
V _ =
The formula rearranged in this way can easily produce the height of the rectangular prism when the volume length and width are known
Reflect
1 Using the formula for a rectangular prism rewrite the formula to solve for ℓ
ℓw
h
Module 2 67 Lesson 3
23 Solving for a VariableEssential Question How do you rewrite formulas and literal equations
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otosCorb
is
Explain 1 Rearranging Scientific FormulasUse inverse operations to isolate the unknown variable in a scientific formula
The formula for density is D = m __ V Lead has a very high density of 11340 kg m 3 Plastic foam has a very low density of 75 kg m 3 The formula for density can be rearranged to solve for V volume or m mass
Example 1
A A sinker on a fishing line is made of lead and has a volume of 0000015 m 3 What is the mass of the sinker
The density formula can be rearranged to isolate m the mass The values for volume and density can then be substituted into the formula to find the mass
D = m _ V
DV = ( m _ V ) V DV = m
(11340 kg m 3 ) (0000015 m 3 ) = m
017 kg asymp m
B The design for a life preserver requires 03 kilogram of plastic foam to provide proper buoyancy What is the volume of the plastic foam required
Rearrange the density formula to isolate V
D = m _ V
(D) V = m _ V
DV =
DV _ = m _
V =
Now substitute the given values
V = _
V = m 3
Your Turn
2 For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Determine the altitude in feet when t is -275 ∘F and g is 60 ∘F
Module 2 68 Lesson 3
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Explain 2 Rearranging Literal EquationsUsing inverse operations to rearrange literal equations can be applied to any formula The interest formula I = prt is another example of a literal equation In the formula I represents interest p the principal or the initial amount to which interest will be applied r the rate at which interest will be paid and t is the time in years
Example 2
A Find the number of years used in the calculation of a $1000 loan at an interest rate of 5 with interest totaling $600
Solve the formula for t
I = prt
I _ pr = prt
_ pr
I _ pr = t
Substitute the given values Since the interest rate is 5 r = 005$600 __
$1000 middot 005 = t
12 = t
So the length of time for the loan is 12 years
B Determine the interest rate for a $2000 loan that will be paid off in 4 years with interest totaling $640 In order to find the interest rate solve the formula for r
I = prt
I _ = prt _
_ = r
Now substitute the values and simplify
__
( ) ( ) = r
008 = r
So the interest rate is per year
Your Turn
3 The formula y = mx + b is the slope-intercept form of the equation of a line Solve the equation for m
Module 2 69 Lesson 3
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bull Online Homeworkbull Hints and Helpbull Extra Practice
Solve for the indicated variable in each mathematical formula
1 C = 2πr for r 2 A = 1 __ 2 bh for b 3 y = mx + b for x
4 A = 1 __ 2 (a + b)h for h 5 V = πr2h for h 6 SA = 2πr2 + 2πrh for h
Solve for the indicated variable in each scientific formula
7 d = rt for t 8 PV = nRT for T
9 A = FV - OV _______ T for OV 10 C = Wtc _ 1000 for W
Evaluate Homework and Practice
Elaborate
4 Discussion What could be a reason for isolating a variable in a literal equation
5 Describe a situation in which a formula could be used more easily if it were rearranged Include the formula in your description
6 Essential Question Check-In How do you isolate a variable
Module 2 70 Lesson 3
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mag
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cean
C
orb
is
Solve for the indicated variable in each literal equation
11 2p + 5r = q for p 12 -10 = xy + z for x 13 a __ b = c for b
14 h - 4 _ j = k for j 15 x __ 5 - g = a for x 16 5p + 9c = p for c
17 2 __ 5 (z + 1) = y for z 18 g (h + 2 __ 3 ) = 1 for h 19 a(n - 3) + 8 = bn for n
20 Which is a possible way to rewrite the equation y = 3x + 3b to solve for b
A b = y - 3x
_ 3 C b = y - 3
_____ 3x
B b = 3(y - 3x) D b = x(y - 3)
21 Sports To find a baseball pitcherrsquos earned run average (ERA) you can use the formula Ei = 9r in which E represents ERA i represents the number of innings pitched and r represents the number of earned runs allowed Solve the equation for E What is a pitcherrsquos ERA if he allows 5 earned runs in 18 innings pitched
22 Meteorology For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Solve the equation for a If the atmospheric temperature is -655 ∘F and the ground temperature is 57 ∘F what is the altitude
Module 2 71 Lesson 3
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oug
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Rand
y D
uch
aineA
lamy
HOT Focus on Higher Order Thinking
23 Explain the Error A student was asked to use the formula for the perimeter of a rectangle P = 2ℓ + 2w to solve for ℓ The student came up with an answer P - 2w = 2ℓ What error did the student make Explain Then solve for ℓ
24 Multi-Step The formula c = 5p + 215 relates c the total cost in dollars of hosting a birthday party at a skating rink to p the number of people attending If Alliersquos parents are willing to spend $300 for a party how many people can attend
25 Multi-Step The formula for the area of a triangle is A = 1 __ 2 bh in which b represents the length of thebase and h represents the height If a triangle has an area of 192 mm2 and the height is 12 mm what is the measure of the base
Lesson Performance TaskThe following table shows the average low temperatures in Fahrenheit for the city of Boston for several months during the year The formula F = 9 __ 5 C + 32 allows you to determine the temperature in Fahrenheit when given the temperature in Celsius
MonthTemperature in
FahrenheitTemperature in
Celsius
January 22deg
April 41deg
July 65deg
October 47deg
December 28deg
a Use the information given to determine the average low temperatures in Celsius
b Would it ever be possible for the temperature in Celsius to have a greater value than the temperature in Fahrenheit Explain why or why not
Module 2 72 Lesson 3
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Name Class Date
Resource Locker
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oug
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Mif
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Com
pan
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mag
e cr
edit
s copy
Patr
ick
Lan
eSo
mos
Imag
esC
orb
is
Explore Creating Inequalities from Verbal DescriptionsAn inequality is a statement that compares two expressions that are not strictly equal by using one of the following inequality signs
Symbol Meaning
lt is less than
le is less than or equal to
gt is greater than
ge is greater than or equal to
ne is not equal to
You have probably seen a sign at an amusement park saying something like ldquoYou must be at least 48 inches tall to ride this riderdquo This statement could be written as h ge 48 in where h represents the height of a person allowed to ride
Nora is planning a birthday party for her little sister Colleen Norarsquos budget will allow her to spend no more than $50 for party supplies Eight children including Colleen will attend the party and Nora wants to determine how much she could spend on party favors for each child She will also purchase a cake for $10 Write an inequality that represents the situation and find possible solutions
A First let c represent the cost of a party favor for each child Write an expression for the total cost of the party as a function of c
c +
B Which inequality symbol should be used to represent the phrase ldquono more thanrdquo
C Write the inequality that represents Norarsquos budget goal
8c + 10 le
D Suppose Nora finds party favors that cost $4 each Use a value of 4 for c and check to see if this inequality is true
8 middot 4 + 10 le 50
le 50
Module 2 73 Lesson 4
24 Creating and Solving Inequalities
Essential Question How do you write and solve an inequality that represents a real-world situation
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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pany
Is the inequality true
Could Nora buy $6 party favors for all of her guests without going over budget
Reflect
1 Why does an inequality represent Norarsquos budget calculation better than an equation
2 The solution set of an inequality consists of all values that make the statement true Describe the whole dollar amounts that are in the solution set for this situation
Explain 1 Creating and Solving Inequalities Involving the Distributive Property
You may need to use the Distributive Property before you can solve an inequality
Distributive Property If a b and c are real numbers then a(b + c) = ab + ac
The inequality sign must be reversed when multiplying or dividing both sides of an inequality by a negative number
Example 1
A Trina is buying 12 shirts for the drama club She will choose a style for the blank shirts and then pay an additional charge of $275 for each shirt to have the club logo If Trina cannot spend more than $99 how much can she spend on each blank shirt Write and solve an inequality to find the possible cost of each blank shirt
Let s represent the cost of each blank shirt
Write an inequality to represent the situation 12(s + 275) le 99
Use the Distributive Property 12s + 33 le 99
Subtraction Property of Inequality 12s + 33 - 33 le 99 - 33
Simplify 12s le 66
Division Property of Inequality 12s ___ 12 le 66 __ 12
Simplify s le 55
Module 2 74 Lesson 4
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pan
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Check your answer
Since s le 55 check a smaller number 12(5 + 275) le 99
Trina can order blank shirts that cost $550 or less 93 le 99 true
B Sergio needs to buy gifts for 8 friends He wants to give the same gift to all his friends and he plans to have the gifts wrapped for an additional charge of $150 each If Sergio spends at least $70 he will receive free shipping on his order Write and solve an inequality to determine how much Sergio needs to spend on each gift in order to receive free shipping
Let g be the cost of one gift
Write an inequality to represent the situation ( g + ) ge 70
Use the Distributive Property g + ge 70
Subtraction Property of Inequality g + 12 - ge 70 -
Simplify 8g ge
Division Property of Inequality 8g _
ge 58 _
Simplify g ge
Check your answer
Since g ge 725 check a larger number 8(8 + 150) ge 70
Sergio must spend at least on each gift ge 70
Reflect
3 Discussion Why is the first step in solving the inequality to use the Distributive Property instead of working inside the parentheses
Your Turn
4 Zachary is planning to send a video game to each of his two brothers If he buys the same game for both brothers and pays $475 to ship each game how much can he spend on each game without spending more than $100 Write and solve an inequality for this situation
Solve each inequality
5 4 _ 3 (6x + 9) lt 4 6 -2 ( 1 _ 4 x + 2 ) ge 5
Module 2 75 Lesson 4
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Explain 2 Creating and Solving Inequalities with Variables on Both Sides
Some inequalities have variable terms on both sides of the inequality symbol You can solve these inequalities the same way you solved equations with variables on both sides Use the properties of inequality to collect all the variable terms on one side and all the constant terms on the other side
Example 2
A The Daily Info charges a fee of $650 plus $80 per week to run an ad The Peoplersquos Paper charges $145 per week For how many weeks must an ad run for the total cost at the Daily Info to be less expensive than the cost at the Peoplersquos Paper Let w be the number of weeks the ad runs in the paper
Write an inequality to represent the situation 650 + 80w lt 145w
Subtraction Property of Inequality 650 + 80w - 80w lt 145w - 80w
Simplify 650 lt 65w
Division Property of Inequality 650 _ 65 lt 65w _ 65
Simplify 10 lt w
The total cost at the Daily Info is less than the cost at the Peoplersquos Paper if the ad runs for more than 10 weeks
B The Home Cleaning Company charges $312 to power-wash the siding of a house plus $12 for each window Power Clean charges $36 per window and the price includes power-washing the siding How many windows must a house have to make the total cost from The Home Cleaning Company less expensive than Power Clean Let w be the number of windows
Write an inequality to represent the situation +12w lt 36w
Subtraction Property of Inequality 312 + 12w - lt 36w -
Simplify 312 lt
Division Property of Inequality 312 _ lt 24w _
Simplify lt w
A house must have more than 13 windows for The Home Cleaning Company to be less expensive than Power Clean
Reflect
7 How would the final inequality change if you divided by ndash24 in the next to last step
Your Turn
8 The school band will sell pizzas to raise money for new uniforms The supplier charges $100 plus $4 per pizza The band members sell the pizzas for $7 each Write and solve an inequality to find how many pizzas the band members will have to sell to make a profit
Module 2 76 Lesson 4
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Elaborate
9 Which inequality symbol would you use to represent the following words or phrases Can you come up with more examples
a at most b farther than c younger than d up to
10 Discussion How are the steps to solving an inequality similar to those for solving an equation How are they different
11 Essential Question Check-In How can you write an inequality that represents a real-world situation
Write an inequality that represents the description and then solve
1 Max has more than 5 carrots (number of carrots Max has = c)
2 Brigitte is shorter than 5 feet (Brigittersquos height = h)
3 Twice a number (x) is less than 10 4 Six more than five times a number (x) is at least twenty-one
5 Dave has $15 to spend on an $8 book and two birthday cards (c) for his friends How much can he spend on each card if he buys the same card for each friend
6 Toni can carry up to 18 lb in her backpack Her lunch weighs 1 lb her gym clothes weigh 2 lb and her books (b) weigh 3 lb each How many books can she carry in her backpack
Evaluate Homework and Practice
bull Online Homeworkbull Hints and Helpbull Extra Practice
Module 2 77 Lesson 4
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Solve each inequality
7 3 (x - 2) gt -3 8 5 + 5 (x + 4) le 20 9 3 + 1 _ 2 (3 - x) lt -7
10 3 (x + 6) - 2 (x + 2) ge 10 11 5 (3 - x) -4 (2 - 3x) gt 2 12 1 _ 2 (4x - 2) - 2 _ 3 (6x + 9) le 4
13 x + 1 gt -5 (7 - 2x) 14 5 _ 3 (6x + 3) le 2x - 7
15 2x le - 2 __ 3 (4x + 4) 16 1 __ 2 (-2x - 10) gt 3 (4 - 6x)
17 -5 - 3x ge 2 (10 + 2x) + 3 18 -3 (9x + 20) ge 15x - 20
19 8 ( 1 _ 4 x - 3) + 24 lt 4 ( x + 5 ) 20 6x - 2 (x + 2) gt 2 - 3 (x + 3)
Module 2 78 Lesson 4
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21 Physics A crane cable can support a maximum load of 15000 kg If a bucket has a mass of 2000 kg and gravel has a mass of 1500 kg for every cubic meter how many cubic meters of gravel (g) can be safely lifted by the crane
22 Find the solution set of each inequality below and then determine which inequalities have the same solution set as 1 _ 3 ( -5x - 3 ) lt 14
a 1 _ 3 (5x + 3) gt -14 b 2 _ 5 (10x + 20) gt 44
c - 2 _ 5 (10x + 20) lt -44 d - 1 _ 3 (5x + 3) lt 14
e 2 _ 5 (10x - 20) gt -44 f 1 _ 3 (5x + 3) lt -14
HOT Focus on Higher Order Thinking
23 Explain the Error Sven is trying to find the maximum amount of time he can spend practicing the five scales of piano music he is supposed to be working on He has 60 minutes to practice piano and would like to spend at least 35 minutes playing songs instead of practicing scales So Sven sets up the following inequality where t is the number of minutes he spends on each scale and solves it
60 - 5t le 35-5t le -25
t ge 5
Sven has concluded that he should spend 5 minutes or more on each scale Is this correct If not what mistake did he make Then solve for the correct answer
Module 2 79 Lesson 4
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24 Critical Thinking Anika wants to determine the maximum number of tulip bulbs (t) she can purchase if each bulb costs $150 She will also need to purchase separate pots for each bulb at $125 each and a bag of potting soil for $1000 Set up an inequality to determine how many tulip bulbs Anika can purchase without spending more than $2000 and solve it Can Anika buy exactly enough bulbs and pots to spend the full $2000 Explain Can you think of a better inequality to describe the answer
25 Geometry The area of the triangle shown is no more than 10 square inches
a Write an inequality that can be used to find x
b Solve the inequality from part a c What is the maximum height of the triangle
Lesson Performance TaskWhen planning an airplane route the trip planner must be careful to consider the range the aircraft can travel and the availability of airports to stop and refuel
A large commercial jet airplane burns approximately 5 gallons of fuel per mile flown plus about 8500 gallons of fuel per trip to reach cruising altitude With a useable fuel capacity of 50000 gallons (there is additional fuel reserved for emergencies) describe the acceptable distance for which an airline could establish a non-stop flight
For flights originating from Chicago determine which cities could be safely reached by a non-stop flight
City Distance from Chicago (miles)
Bangalore India 8530
Jakarta Indonesia 9810
Johannesburg South Africa 8680
Moscow Russia 4970
Paris France 4130
Perth Australia 10970
Tokyo Japan 6300
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eva O
lesiaShutterstock
(2x - 3) in
4 in
Module 2 80 Lesson 4
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Name Class Date
Resource Locker
Explore Truth Tables and Compound StatementsA compound statement is formed by combining two or more simple statements A compound statement can be true or false A compound statement involving AND is true when both simple statements are true A compound statement involving OR is true when either one simple statement or both are true
A Complete the truth table
P QP
True or FalseQ
True or FalseP AND Q
True or False
A dog is a mammal Red is a color
A dog is a mammal Red is not a color
A dog is a fish Red is a color
A dog is a fish Red is not a color
B P AND Q is true when
C Complete the truth table
P QP
True or FalseQ
True or FalseP OR Q
True or False
1 is an odd number 2 is an even number
1 is an odd number 2 is an odd number
1 is an even number 2 is an even number
1 is an even number 2 is an odd number
D P OR Q is true when
Reflect
1 Give two simple statements P and Q for which P AND Q is false and P OR Q is true
Module 2 81 Lesson 5
25 Creating and Solving Compound Inequalities
Essential Question How can you solve a compound inequality and graph the solution set
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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Explain 1 Solving Compound Inequalities Involving ANDCombining two or more simple inequalities forms a compound inequality The graph of a compound inequality involving AND is the intersection or the overlapping region of the simple inequality graphs
Compound Inequalities AND
Words Algebra Graph
All real numbers greater than 2AND less than 6
x gt 2 AND x lt 62 lt x lt 6
All real numbers greater than or equal to 2 AND less than or equal to 6
x ge 2 AND x le 62 le x le 6
Example 1 Solve each compound inequality and graph the solutions
A 4 le x + 2 le 8
4 le x + 2 AND x + 2 le 8 Write the compound inequality using AND
4 - 2 le x + 2 - 2 x + 2 - 2 le 8 - 2 Subtract 2 from both sides of each simple inequality
2 le x x le 6 Simplify
Graph 2 le x
Graph x le 6
Graph the intersection by finding where the two graphs overlap
B -5 le 2x + 3 lt 9
-5 - le 2x + 3 - lt 9 - Subtract from each part of the inequality
le 2x lt Simplify
-8 _ le 2x _ lt 6 _ Divide each part of the inequality by
le x lt Simplify
Graph -4 le x
Graph x lt 3
Graph the intersection by finding where the two graphs overlap -1 0 1 2 3 4 5-5-4 -3 -2
0 2 4 6 8 10 12-8-6-4 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 82 Lesson 5
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Reflect
2 Discussion Explain why 2 le x le 6 can be considered the short method for writing the AND compound inequality x ge 2 AND x le 6
YourTurn
Solve each compound inequality and graph the solutions
3 -2 lt x - 3 lt 5
4 -10 lt 3x + 2 le 8
Explain 2 Solving Compound Inequalities Involving ORThe graph of a compound inequality involving OR is the union or the combined region of the simple inequality graphs
Compound Inequalities OR
Words Algebra Graph
All real numbers less than 2OR greater than 6
x lt 2 OR x gt 6
All real numbers less than or equal to 2OR greater than or equal to 6
x le 2 OR x ge 6
-1 0 1 2 3 4 5-5-4 -3 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 83 Lesson 5
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Example 2 Solve each compound inequality and graph the solutions
A -4 + x gt 1 OR -4 + x lt -3
-4 + x gt 1 OR -4 + x lt -3 Write the compound inequality using OR
-4 + 4 + x gt 1 + 4 -4 + 4 + x lt -3 + 4 Add 4 to both sides of each simple inequality
x gt 5 x lt 1 Simplify
Graph x gt 5
Graph x lt 1
Graph the union by combining the graphs
B 2x le 6 OR 3x gt 12
2x le 6 OR 3x gt 12 Write the compound inequality using OR
2x _ le 6 _ OR 3x _ gt 12 _ Divide the first simple inequality by
x le OR x gt
Graph x le 3
Graph x gt 4
Graph the union by combining the graphs
Reflect
5 Critical Thinking What kind of compound inequality has no solution
Divide the second simple inequality by
Simplify
0 1 2 3 4 5 6-4 -3 -2 -1
-0 1 2 3 4 5 6-4 -3 -2 -1
Module 2 84 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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Your Turn
Solve each compound inequality and graph the solutions
6 x - 5 ge -2 OR x -5 le -6
7 4x -1 lt 15 OR 8x ge 48
Explain 3 Creating Compound Inequalities From GraphsGiven a number line graph with a solution set graphed you can create a compound inequality to fit the graph
Example 3 Write the compound inequality shown by each graph
A
The shaded portion of the graph is not between two values so the compound inequality involves OR
On the left the graph shows an arrow pointing left from -1 and a solid circle so use le
The inequality is x le -1
On the right the graph shows an arrow pointing right from 7 and a solid circle so use ge
The inequality is x ge 7
The compound inequality is x le -1 OR x ge 7
B
The graph is shaded between the values and so the compound inequality involves AND
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The compound inequality is
-1 0 1 2 3 4 5-5-4 -3 -2
4 5 6 7 8 9 100 1 2 3
2 3 4 5 6 7 8-2 -1 0 1
10 2 3 4 5 6 7 8 9-1
Module 2 85 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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Reflect
8 What is a short method to write the compound inequality x ge 0 AND x lt 6
Your Turn
Write the compound inequality shown by each graph
9
10
Explain 4 Expressing Acceptable Levels with Compound Inequalities
You can express quality-controls levels in real-world problems using compound inequalities
Example 4 Write a compound inequality to represent the indicated quality-control level and graph the solutions
A The recommended pH level for swimming pool water is between 72 and 76 inclusive
Let p be the pH level of swimming pool water
72 is less than or equal to pH level is less than or equal to 76
72 le p le 76
The compound inequality is 72 le p le 76
Graph the solutions
0-10 -8-9 -7-6 -5-4 -3 -2 -1
71 72 73 74 75 76 77 78 79 8070
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 86 Lesson 5
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B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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pany
bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
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Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
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Than
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tanisakornA
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Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
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HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
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The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
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Name Class Date
Resource Locker
Explore Rearranging Mathematical FormulasLiteral Equations are equations that contain two or more variables There are many literal equations in the form of math science and engineering formulas These formulas may seem like they can only be solved for the variable that is isolated on one side of the formula By using inverse operations and the properties of equality a formula can be rearranged so any variable in the formula can be isolated It is no different than how equations are solved by using inverse operations and the properties of equality
How can you solve the equation 42 = 6x
A42 _ = 6x _ What is the reason for dividing
Why divide by
= x By rearranging the equation x was isolated and the solution was found
The mathematical formula for the volume of a rectangular prism B = Vh or V = ℓwh is a literal equation V represents volume ℓ represents length w represents width and h represents height Using inverse operations the formula can be rearranged to solve for any one of the variables that might be unknown Like solving for x a formula can be rearranged to isolate a variable
B In the formula V = ℓwh the variable h needs to be isolated
The operation of is used in the formula The inverse
operation should be used
to isolate
C V _____ = ℓwh _____
V _ =
The formula rearranged in this way can easily produce the height of the rectangular prism when the volume length and width are known
Reflect
1 Using the formula for a rectangular prism rewrite the formula to solve for ℓ
ℓw
h
Module 2 67 Lesson 3
23 Solving for a VariableEssential Question How do you rewrite formulas and literal equations
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Photo
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hyAurora Ph
otosCorb
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Explain 1 Rearranging Scientific FormulasUse inverse operations to isolate the unknown variable in a scientific formula
The formula for density is D = m __ V Lead has a very high density of 11340 kg m 3 Plastic foam has a very low density of 75 kg m 3 The formula for density can be rearranged to solve for V volume or m mass
Example 1
A A sinker on a fishing line is made of lead and has a volume of 0000015 m 3 What is the mass of the sinker
The density formula can be rearranged to isolate m the mass The values for volume and density can then be substituted into the formula to find the mass
D = m _ V
DV = ( m _ V ) V DV = m
(11340 kg m 3 ) (0000015 m 3 ) = m
017 kg asymp m
B The design for a life preserver requires 03 kilogram of plastic foam to provide proper buoyancy What is the volume of the plastic foam required
Rearrange the density formula to isolate V
D = m _ V
(D) V = m _ V
DV =
DV _ = m _
V =
Now substitute the given values
V = _
V = m 3
Your Turn
2 For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Determine the altitude in feet when t is -275 ∘F and g is 60 ∘F
Module 2 68 Lesson 3
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Explain 2 Rearranging Literal EquationsUsing inverse operations to rearrange literal equations can be applied to any formula The interest formula I = prt is another example of a literal equation In the formula I represents interest p the principal or the initial amount to which interest will be applied r the rate at which interest will be paid and t is the time in years
Example 2
A Find the number of years used in the calculation of a $1000 loan at an interest rate of 5 with interest totaling $600
Solve the formula for t
I = prt
I _ pr = prt
_ pr
I _ pr = t
Substitute the given values Since the interest rate is 5 r = 005$600 __
$1000 middot 005 = t
12 = t
So the length of time for the loan is 12 years
B Determine the interest rate for a $2000 loan that will be paid off in 4 years with interest totaling $640 In order to find the interest rate solve the formula for r
I = prt
I _ = prt _
_ = r
Now substitute the values and simplify
__
( ) ( ) = r
008 = r
So the interest rate is per year
Your Turn
3 The formula y = mx + b is the slope-intercept form of the equation of a line Solve the equation for m
Module 2 69 Lesson 3
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bull Online Homeworkbull Hints and Helpbull Extra Practice
Solve for the indicated variable in each mathematical formula
1 C = 2πr for r 2 A = 1 __ 2 bh for b 3 y = mx + b for x
4 A = 1 __ 2 (a + b)h for h 5 V = πr2h for h 6 SA = 2πr2 + 2πrh for h
Solve for the indicated variable in each scientific formula
7 d = rt for t 8 PV = nRT for T
9 A = FV - OV _______ T for OV 10 C = Wtc _ 1000 for W
Evaluate Homework and Practice
Elaborate
4 Discussion What could be a reason for isolating a variable in a literal equation
5 Describe a situation in which a formula could be used more easily if it were rearranged Include the formula in your description
6 Essential Question Check-In How do you isolate a variable
Module 2 70 Lesson 3
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cean
C
orb
is
Solve for the indicated variable in each literal equation
11 2p + 5r = q for p 12 -10 = xy + z for x 13 a __ b = c for b
14 h - 4 _ j = k for j 15 x __ 5 - g = a for x 16 5p + 9c = p for c
17 2 __ 5 (z + 1) = y for z 18 g (h + 2 __ 3 ) = 1 for h 19 a(n - 3) + 8 = bn for n
20 Which is a possible way to rewrite the equation y = 3x + 3b to solve for b
A b = y - 3x
_ 3 C b = y - 3
_____ 3x
B b = 3(y - 3x) D b = x(y - 3)
21 Sports To find a baseball pitcherrsquos earned run average (ERA) you can use the formula Ei = 9r in which E represents ERA i represents the number of innings pitched and r represents the number of earned runs allowed Solve the equation for E What is a pitcherrsquos ERA if he allows 5 earned runs in 18 innings pitched
22 Meteorology For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Solve the equation for a If the atmospheric temperature is -655 ∘F and the ground temperature is 57 ∘F what is the altitude
Module 2 71 Lesson 3
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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Rand
y D
uch
aineA
lamy
HOT Focus on Higher Order Thinking
23 Explain the Error A student was asked to use the formula for the perimeter of a rectangle P = 2ℓ + 2w to solve for ℓ The student came up with an answer P - 2w = 2ℓ What error did the student make Explain Then solve for ℓ
24 Multi-Step The formula c = 5p + 215 relates c the total cost in dollars of hosting a birthday party at a skating rink to p the number of people attending If Alliersquos parents are willing to spend $300 for a party how many people can attend
25 Multi-Step The formula for the area of a triangle is A = 1 __ 2 bh in which b represents the length of thebase and h represents the height If a triangle has an area of 192 mm2 and the height is 12 mm what is the measure of the base
Lesson Performance TaskThe following table shows the average low temperatures in Fahrenheit for the city of Boston for several months during the year The formula F = 9 __ 5 C + 32 allows you to determine the temperature in Fahrenheit when given the temperature in Celsius
MonthTemperature in
FahrenheitTemperature in
Celsius
January 22deg
April 41deg
July 65deg
October 47deg
December 28deg
a Use the information given to determine the average low temperatures in Celsius
b Would it ever be possible for the temperature in Celsius to have a greater value than the temperature in Fahrenheit Explain why or why not
Module 2 72 Lesson 3
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
Name Class Date
Resource Locker
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oug
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Mif
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Har
cour
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Com
pan
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mag
e cr
edit
s copy
Patr
ick
Lan
eSo
mos
Imag
esC
orb
is
Explore Creating Inequalities from Verbal DescriptionsAn inequality is a statement that compares two expressions that are not strictly equal by using one of the following inequality signs
Symbol Meaning
lt is less than
le is less than or equal to
gt is greater than
ge is greater than or equal to
ne is not equal to
You have probably seen a sign at an amusement park saying something like ldquoYou must be at least 48 inches tall to ride this riderdquo This statement could be written as h ge 48 in where h represents the height of a person allowed to ride
Nora is planning a birthday party for her little sister Colleen Norarsquos budget will allow her to spend no more than $50 for party supplies Eight children including Colleen will attend the party and Nora wants to determine how much she could spend on party favors for each child She will also purchase a cake for $10 Write an inequality that represents the situation and find possible solutions
A First let c represent the cost of a party favor for each child Write an expression for the total cost of the party as a function of c
c +
B Which inequality symbol should be used to represent the phrase ldquono more thanrdquo
C Write the inequality that represents Norarsquos budget goal
8c + 10 le
D Suppose Nora finds party favors that cost $4 each Use a value of 4 for c and check to see if this inequality is true
8 middot 4 + 10 le 50
le 50
Module 2 73 Lesson 4
24 Creating and Solving Inequalities
Essential Question How do you write and solve an inequality that represents a real-world situation
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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Is the inequality true
Could Nora buy $6 party favors for all of her guests without going over budget
Reflect
1 Why does an inequality represent Norarsquos budget calculation better than an equation
2 The solution set of an inequality consists of all values that make the statement true Describe the whole dollar amounts that are in the solution set for this situation
Explain 1 Creating and Solving Inequalities Involving the Distributive Property
You may need to use the Distributive Property before you can solve an inequality
Distributive Property If a b and c are real numbers then a(b + c) = ab + ac
The inequality sign must be reversed when multiplying or dividing both sides of an inequality by a negative number
Example 1
A Trina is buying 12 shirts for the drama club She will choose a style for the blank shirts and then pay an additional charge of $275 for each shirt to have the club logo If Trina cannot spend more than $99 how much can she spend on each blank shirt Write and solve an inequality to find the possible cost of each blank shirt
Let s represent the cost of each blank shirt
Write an inequality to represent the situation 12(s + 275) le 99
Use the Distributive Property 12s + 33 le 99
Subtraction Property of Inequality 12s + 33 - 33 le 99 - 33
Simplify 12s le 66
Division Property of Inequality 12s ___ 12 le 66 __ 12
Simplify s le 55
Module 2 74 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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pan
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Check your answer
Since s le 55 check a smaller number 12(5 + 275) le 99
Trina can order blank shirts that cost $550 or less 93 le 99 true
B Sergio needs to buy gifts for 8 friends He wants to give the same gift to all his friends and he plans to have the gifts wrapped for an additional charge of $150 each If Sergio spends at least $70 he will receive free shipping on his order Write and solve an inequality to determine how much Sergio needs to spend on each gift in order to receive free shipping
Let g be the cost of one gift
Write an inequality to represent the situation ( g + ) ge 70
Use the Distributive Property g + ge 70
Subtraction Property of Inequality g + 12 - ge 70 -
Simplify 8g ge
Division Property of Inequality 8g _
ge 58 _
Simplify g ge
Check your answer
Since g ge 725 check a larger number 8(8 + 150) ge 70
Sergio must spend at least on each gift ge 70
Reflect
3 Discussion Why is the first step in solving the inequality to use the Distributive Property instead of working inside the parentheses
Your Turn
4 Zachary is planning to send a video game to each of his two brothers If he buys the same game for both brothers and pays $475 to ship each game how much can he spend on each game without spending more than $100 Write and solve an inequality for this situation
Solve each inequality
5 4 _ 3 (6x + 9) lt 4 6 -2 ( 1 _ 4 x + 2 ) ge 5
Module 2 75 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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Explain 2 Creating and Solving Inequalities with Variables on Both Sides
Some inequalities have variable terms on both sides of the inequality symbol You can solve these inequalities the same way you solved equations with variables on both sides Use the properties of inequality to collect all the variable terms on one side and all the constant terms on the other side
Example 2
A The Daily Info charges a fee of $650 plus $80 per week to run an ad The Peoplersquos Paper charges $145 per week For how many weeks must an ad run for the total cost at the Daily Info to be less expensive than the cost at the Peoplersquos Paper Let w be the number of weeks the ad runs in the paper
Write an inequality to represent the situation 650 + 80w lt 145w
Subtraction Property of Inequality 650 + 80w - 80w lt 145w - 80w
Simplify 650 lt 65w
Division Property of Inequality 650 _ 65 lt 65w _ 65
Simplify 10 lt w
The total cost at the Daily Info is less than the cost at the Peoplersquos Paper if the ad runs for more than 10 weeks
B The Home Cleaning Company charges $312 to power-wash the siding of a house plus $12 for each window Power Clean charges $36 per window and the price includes power-washing the siding How many windows must a house have to make the total cost from The Home Cleaning Company less expensive than Power Clean Let w be the number of windows
Write an inequality to represent the situation +12w lt 36w
Subtraction Property of Inequality 312 + 12w - lt 36w -
Simplify 312 lt
Division Property of Inequality 312 _ lt 24w _
Simplify lt w
A house must have more than 13 windows for The Home Cleaning Company to be less expensive than Power Clean
Reflect
7 How would the final inequality change if you divided by ndash24 in the next to last step
Your Turn
8 The school band will sell pizzas to raise money for new uniforms The supplier charges $100 plus $4 per pizza The band members sell the pizzas for $7 each Write and solve an inequality to find how many pizzas the band members will have to sell to make a profit
Module 2 76 Lesson 4
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Elaborate
9 Which inequality symbol would you use to represent the following words or phrases Can you come up with more examples
a at most b farther than c younger than d up to
10 Discussion How are the steps to solving an inequality similar to those for solving an equation How are they different
11 Essential Question Check-In How can you write an inequality that represents a real-world situation
Write an inequality that represents the description and then solve
1 Max has more than 5 carrots (number of carrots Max has = c)
2 Brigitte is shorter than 5 feet (Brigittersquos height = h)
3 Twice a number (x) is less than 10 4 Six more than five times a number (x) is at least twenty-one
5 Dave has $15 to spend on an $8 book and two birthday cards (c) for his friends How much can he spend on each card if he buys the same card for each friend
6 Toni can carry up to 18 lb in her backpack Her lunch weighs 1 lb her gym clothes weigh 2 lb and her books (b) weigh 3 lb each How many books can she carry in her backpack
Evaluate Homework and Practice
bull Online Homeworkbull Hints and Helpbull Extra Practice
Module 2 77 Lesson 4
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Solve each inequality
7 3 (x - 2) gt -3 8 5 + 5 (x + 4) le 20 9 3 + 1 _ 2 (3 - x) lt -7
10 3 (x + 6) - 2 (x + 2) ge 10 11 5 (3 - x) -4 (2 - 3x) gt 2 12 1 _ 2 (4x - 2) - 2 _ 3 (6x + 9) le 4
13 x + 1 gt -5 (7 - 2x) 14 5 _ 3 (6x + 3) le 2x - 7
15 2x le - 2 __ 3 (4x + 4) 16 1 __ 2 (-2x - 10) gt 3 (4 - 6x)
17 -5 - 3x ge 2 (10 + 2x) + 3 18 -3 (9x + 20) ge 15x - 20
19 8 ( 1 _ 4 x - 3) + 24 lt 4 ( x + 5 ) 20 6x - 2 (x + 2) gt 2 - 3 (x + 3)
Module 2 78 Lesson 4
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21 Physics A crane cable can support a maximum load of 15000 kg If a bucket has a mass of 2000 kg and gravel has a mass of 1500 kg for every cubic meter how many cubic meters of gravel (g) can be safely lifted by the crane
22 Find the solution set of each inequality below and then determine which inequalities have the same solution set as 1 _ 3 ( -5x - 3 ) lt 14
a 1 _ 3 (5x + 3) gt -14 b 2 _ 5 (10x + 20) gt 44
c - 2 _ 5 (10x + 20) lt -44 d - 1 _ 3 (5x + 3) lt 14
e 2 _ 5 (10x - 20) gt -44 f 1 _ 3 (5x + 3) lt -14
HOT Focus on Higher Order Thinking
23 Explain the Error Sven is trying to find the maximum amount of time he can spend practicing the five scales of piano music he is supposed to be working on He has 60 minutes to practice piano and would like to spend at least 35 minutes playing songs instead of practicing scales So Sven sets up the following inequality where t is the number of minutes he spends on each scale and solves it
60 - 5t le 35-5t le -25
t ge 5
Sven has concluded that he should spend 5 minutes or more on each scale Is this correct If not what mistake did he make Then solve for the correct answer
Module 2 79 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
24 Critical Thinking Anika wants to determine the maximum number of tulip bulbs (t) she can purchase if each bulb costs $150 She will also need to purchase separate pots for each bulb at $125 each and a bag of potting soil for $1000 Set up an inequality to determine how many tulip bulbs Anika can purchase without spending more than $2000 and solve it Can Anika buy exactly enough bulbs and pots to spend the full $2000 Explain Can you think of a better inequality to describe the answer
25 Geometry The area of the triangle shown is no more than 10 square inches
a Write an inequality that can be used to find x
b Solve the inequality from part a c What is the maximum height of the triangle
Lesson Performance TaskWhen planning an airplane route the trip planner must be careful to consider the range the aircraft can travel and the availability of airports to stop and refuel
A large commercial jet airplane burns approximately 5 gallons of fuel per mile flown plus about 8500 gallons of fuel per trip to reach cruising altitude With a useable fuel capacity of 50000 gallons (there is additional fuel reserved for emergencies) describe the acceptable distance for which an airline could establish a non-stop flight
For flights originating from Chicago determine which cities could be safely reached by a non-stop flight
City Distance from Chicago (miles)
Bangalore India 8530
Jakarta Indonesia 9810
Johannesburg South Africa 8680
Moscow Russia 4970
Paris France 4130
Perth Australia 10970
Tokyo Japan 6300
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eva O
lesiaShutterstock
(2x - 3) in
4 in
Module 2 80 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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Mif
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Har
cour
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pan
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Name Class Date
Resource Locker
Explore Truth Tables and Compound StatementsA compound statement is formed by combining two or more simple statements A compound statement can be true or false A compound statement involving AND is true when both simple statements are true A compound statement involving OR is true when either one simple statement or both are true
A Complete the truth table
P QP
True or FalseQ
True or FalseP AND Q
True or False
A dog is a mammal Red is a color
A dog is a mammal Red is not a color
A dog is a fish Red is a color
A dog is a fish Red is not a color
B P AND Q is true when
C Complete the truth table
P QP
True or FalseQ
True or FalseP OR Q
True or False
1 is an odd number 2 is an even number
1 is an odd number 2 is an odd number
1 is an even number 2 is an even number
1 is an even number 2 is an odd number
D P OR Q is true when
Reflect
1 Give two simple statements P and Q for which P AND Q is false and P OR Q is true
Module 2 81 Lesson 5
25 Creating and Solving Compound Inequalities
Essential Question How can you solve a compound inequality and graph the solution set
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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Explain 1 Solving Compound Inequalities Involving ANDCombining two or more simple inequalities forms a compound inequality The graph of a compound inequality involving AND is the intersection or the overlapping region of the simple inequality graphs
Compound Inequalities AND
Words Algebra Graph
All real numbers greater than 2AND less than 6
x gt 2 AND x lt 62 lt x lt 6
All real numbers greater than or equal to 2 AND less than or equal to 6
x ge 2 AND x le 62 le x le 6
Example 1 Solve each compound inequality and graph the solutions
A 4 le x + 2 le 8
4 le x + 2 AND x + 2 le 8 Write the compound inequality using AND
4 - 2 le x + 2 - 2 x + 2 - 2 le 8 - 2 Subtract 2 from both sides of each simple inequality
2 le x x le 6 Simplify
Graph 2 le x
Graph x le 6
Graph the intersection by finding where the two graphs overlap
B -5 le 2x + 3 lt 9
-5 - le 2x + 3 - lt 9 - Subtract from each part of the inequality
le 2x lt Simplify
-8 _ le 2x _ lt 6 _ Divide each part of the inequality by
le x lt Simplify
Graph -4 le x
Graph x lt 3
Graph the intersection by finding where the two graphs overlap -1 0 1 2 3 4 5-5-4 -3 -2
0 2 4 6 8 10 12-8-6-4 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 82 Lesson 5
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Reflect
2 Discussion Explain why 2 le x le 6 can be considered the short method for writing the AND compound inequality x ge 2 AND x le 6
YourTurn
Solve each compound inequality and graph the solutions
3 -2 lt x - 3 lt 5
4 -10 lt 3x + 2 le 8
Explain 2 Solving Compound Inequalities Involving ORThe graph of a compound inequality involving OR is the union or the combined region of the simple inequality graphs
Compound Inequalities OR
Words Algebra Graph
All real numbers less than 2OR greater than 6
x lt 2 OR x gt 6
All real numbers less than or equal to 2OR greater than or equal to 6
x le 2 OR x ge 6
-1 0 1 2 3 4 5-5-4 -3 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 83 Lesson 5
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Example 2 Solve each compound inequality and graph the solutions
A -4 + x gt 1 OR -4 + x lt -3
-4 + x gt 1 OR -4 + x lt -3 Write the compound inequality using OR
-4 + 4 + x gt 1 + 4 -4 + 4 + x lt -3 + 4 Add 4 to both sides of each simple inequality
x gt 5 x lt 1 Simplify
Graph x gt 5
Graph x lt 1
Graph the union by combining the graphs
B 2x le 6 OR 3x gt 12
2x le 6 OR 3x gt 12 Write the compound inequality using OR
2x _ le 6 _ OR 3x _ gt 12 _ Divide the first simple inequality by
x le OR x gt
Graph x le 3
Graph x gt 4
Graph the union by combining the graphs
Reflect
5 Critical Thinking What kind of compound inequality has no solution
Divide the second simple inequality by
Simplify
0 1 2 3 4 5 6-4 -3 -2 -1
-0 1 2 3 4 5 6-4 -3 -2 -1
Module 2 84 Lesson 5
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Your Turn
Solve each compound inequality and graph the solutions
6 x - 5 ge -2 OR x -5 le -6
7 4x -1 lt 15 OR 8x ge 48
Explain 3 Creating Compound Inequalities From GraphsGiven a number line graph with a solution set graphed you can create a compound inequality to fit the graph
Example 3 Write the compound inequality shown by each graph
A
The shaded portion of the graph is not between two values so the compound inequality involves OR
On the left the graph shows an arrow pointing left from -1 and a solid circle so use le
The inequality is x le -1
On the right the graph shows an arrow pointing right from 7 and a solid circle so use ge
The inequality is x ge 7
The compound inequality is x le -1 OR x ge 7
B
The graph is shaded between the values and so the compound inequality involves AND
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The compound inequality is
-1 0 1 2 3 4 5-5-4 -3 -2
4 5 6 7 8 9 100 1 2 3
2 3 4 5 6 7 8-2 -1 0 1
10 2 3 4 5 6 7 8 9-1
Module 2 85 Lesson 5
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Reflect
8 What is a short method to write the compound inequality x ge 0 AND x lt 6
Your Turn
Write the compound inequality shown by each graph
9
10
Explain 4 Expressing Acceptable Levels with Compound Inequalities
You can express quality-controls levels in real-world problems using compound inequalities
Example 4 Write a compound inequality to represent the indicated quality-control level and graph the solutions
A The recommended pH level for swimming pool water is between 72 and 76 inclusive
Let p be the pH level of swimming pool water
72 is less than or equal to pH level is less than or equal to 76
72 le p le 76
The compound inequality is 72 le p le 76
Graph the solutions
0-10 -8-9 -7-6 -5-4 -3 -2 -1
71 72 73 74 75 76 77 78 79 8070
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 86 Lesson 5
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B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
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bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
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Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
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Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
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oug
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bik
erid
erlo
nd
onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
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The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
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oug
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Photo
grap
hyAurora Ph
otosCorb
is
Explain 1 Rearranging Scientific FormulasUse inverse operations to isolate the unknown variable in a scientific formula
The formula for density is D = m __ V Lead has a very high density of 11340 kg m 3 Plastic foam has a very low density of 75 kg m 3 The formula for density can be rearranged to solve for V volume or m mass
Example 1
A A sinker on a fishing line is made of lead and has a volume of 0000015 m 3 What is the mass of the sinker
The density formula can be rearranged to isolate m the mass The values for volume and density can then be substituted into the formula to find the mass
D = m _ V
DV = ( m _ V ) V DV = m
(11340 kg m 3 ) (0000015 m 3 ) = m
017 kg asymp m
B The design for a life preserver requires 03 kilogram of plastic foam to provide proper buoyancy What is the volume of the plastic foam required
Rearrange the density formula to isolate V
D = m _ V
(D) V = m _ V
DV =
DV _ = m _
V =
Now substitute the given values
V = _
V = m 3
Your Turn
2 For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Determine the altitude in feet when t is -275 ∘F and g is 60 ∘F
Module 2 68 Lesson 3
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Explain 2 Rearranging Literal EquationsUsing inverse operations to rearrange literal equations can be applied to any formula The interest formula I = prt is another example of a literal equation In the formula I represents interest p the principal or the initial amount to which interest will be applied r the rate at which interest will be paid and t is the time in years
Example 2
A Find the number of years used in the calculation of a $1000 loan at an interest rate of 5 with interest totaling $600
Solve the formula for t
I = prt
I _ pr = prt
_ pr
I _ pr = t
Substitute the given values Since the interest rate is 5 r = 005$600 __
$1000 middot 005 = t
12 = t
So the length of time for the loan is 12 years
B Determine the interest rate for a $2000 loan that will be paid off in 4 years with interest totaling $640 In order to find the interest rate solve the formula for r
I = prt
I _ = prt _
_ = r
Now substitute the values and simplify
__
( ) ( ) = r
008 = r
So the interest rate is per year
Your Turn
3 The formula y = mx + b is the slope-intercept form of the equation of a line Solve the equation for m
Module 2 69 Lesson 3
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oug
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bull Online Homeworkbull Hints and Helpbull Extra Practice
Solve for the indicated variable in each mathematical formula
1 C = 2πr for r 2 A = 1 __ 2 bh for b 3 y = mx + b for x
4 A = 1 __ 2 (a + b)h for h 5 V = πr2h for h 6 SA = 2πr2 + 2πrh for h
Solve for the indicated variable in each scientific formula
7 d = rt for t 8 PV = nRT for T
9 A = FV - OV _______ T for OV 10 C = Wtc _ 1000 for W
Evaluate Homework and Practice
Elaborate
4 Discussion What could be a reason for isolating a variable in a literal equation
5 Describe a situation in which a formula could be used more easily if it were rearranged Include the formula in your description
6 Essential Question Check-In How do you isolate a variable
Module 2 70 Lesson 3
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oug
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cour
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mag
e C
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copyO
cean
C
orb
is
Solve for the indicated variable in each literal equation
11 2p + 5r = q for p 12 -10 = xy + z for x 13 a __ b = c for b
14 h - 4 _ j = k for j 15 x __ 5 - g = a for x 16 5p + 9c = p for c
17 2 __ 5 (z + 1) = y for z 18 g (h + 2 __ 3 ) = 1 for h 19 a(n - 3) + 8 = bn for n
20 Which is a possible way to rewrite the equation y = 3x + 3b to solve for b
A b = y - 3x
_ 3 C b = y - 3
_____ 3x
B b = 3(y - 3x) D b = x(y - 3)
21 Sports To find a baseball pitcherrsquos earned run average (ERA) you can use the formula Ei = 9r in which E represents ERA i represents the number of innings pitched and r represents the number of earned runs allowed Solve the equation for E What is a pitcherrsquos ERA if he allows 5 earned runs in 18 innings pitched
22 Meteorology For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Solve the equation for a If the atmospheric temperature is -655 ∘F and the ground temperature is 57 ∘F what is the altitude
Module 2 71 Lesson 3
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
arcourt Publishin
g Com
pany bull Im
age C
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Rand
y D
uch
aineA
lamy
HOT Focus on Higher Order Thinking
23 Explain the Error A student was asked to use the formula for the perimeter of a rectangle P = 2ℓ + 2w to solve for ℓ The student came up with an answer P - 2w = 2ℓ What error did the student make Explain Then solve for ℓ
24 Multi-Step The formula c = 5p + 215 relates c the total cost in dollars of hosting a birthday party at a skating rink to p the number of people attending If Alliersquos parents are willing to spend $300 for a party how many people can attend
25 Multi-Step The formula for the area of a triangle is A = 1 __ 2 bh in which b represents the length of thebase and h represents the height If a triangle has an area of 192 mm2 and the height is 12 mm what is the measure of the base
Lesson Performance TaskThe following table shows the average low temperatures in Fahrenheit for the city of Boston for several months during the year The formula F = 9 __ 5 C + 32 allows you to determine the temperature in Fahrenheit when given the temperature in Celsius
MonthTemperature in
FahrenheitTemperature in
Celsius
January 22deg
April 41deg
July 65deg
October 47deg
December 28deg
a Use the information given to determine the average low temperatures in Celsius
b Would it ever be possible for the temperature in Celsius to have a greater value than the temperature in Fahrenheit Explain why or why not
Module 2 72 Lesson 3
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
Name Class Date
Resource Locker
copy H
oug
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Mif
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cour
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Com
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e cr
edit
s copy
Patr
ick
Lan
eSo
mos
Imag
esC
orb
is
Explore Creating Inequalities from Verbal DescriptionsAn inequality is a statement that compares two expressions that are not strictly equal by using one of the following inequality signs
Symbol Meaning
lt is less than
le is less than or equal to
gt is greater than
ge is greater than or equal to
ne is not equal to
You have probably seen a sign at an amusement park saying something like ldquoYou must be at least 48 inches tall to ride this riderdquo This statement could be written as h ge 48 in where h represents the height of a person allowed to ride
Nora is planning a birthday party for her little sister Colleen Norarsquos budget will allow her to spend no more than $50 for party supplies Eight children including Colleen will attend the party and Nora wants to determine how much she could spend on party favors for each child She will also purchase a cake for $10 Write an inequality that represents the situation and find possible solutions
A First let c represent the cost of a party favor for each child Write an expression for the total cost of the party as a function of c
c +
B Which inequality symbol should be used to represent the phrase ldquono more thanrdquo
C Write the inequality that represents Norarsquos budget goal
8c + 10 le
D Suppose Nora finds party favors that cost $4 each Use a value of 4 for c and check to see if this inequality is true
8 middot 4 + 10 le 50
le 50
Module 2 73 Lesson 4
24 Creating and Solving Inequalities
Essential Question How do you write and solve an inequality that represents a real-world situation
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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pany
Is the inequality true
Could Nora buy $6 party favors for all of her guests without going over budget
Reflect
1 Why does an inequality represent Norarsquos budget calculation better than an equation
2 The solution set of an inequality consists of all values that make the statement true Describe the whole dollar amounts that are in the solution set for this situation
Explain 1 Creating and Solving Inequalities Involving the Distributive Property
You may need to use the Distributive Property before you can solve an inequality
Distributive Property If a b and c are real numbers then a(b + c) = ab + ac
The inequality sign must be reversed when multiplying or dividing both sides of an inequality by a negative number
Example 1
A Trina is buying 12 shirts for the drama club She will choose a style for the blank shirts and then pay an additional charge of $275 for each shirt to have the club logo If Trina cannot spend more than $99 how much can she spend on each blank shirt Write and solve an inequality to find the possible cost of each blank shirt
Let s represent the cost of each blank shirt
Write an inequality to represent the situation 12(s + 275) le 99
Use the Distributive Property 12s + 33 le 99
Subtraction Property of Inequality 12s + 33 - 33 le 99 - 33
Simplify 12s le 66
Division Property of Inequality 12s ___ 12 le 66 __ 12
Simplify s le 55
Module 2 74 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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Check your answer
Since s le 55 check a smaller number 12(5 + 275) le 99
Trina can order blank shirts that cost $550 or less 93 le 99 true
B Sergio needs to buy gifts for 8 friends He wants to give the same gift to all his friends and he plans to have the gifts wrapped for an additional charge of $150 each If Sergio spends at least $70 he will receive free shipping on his order Write and solve an inequality to determine how much Sergio needs to spend on each gift in order to receive free shipping
Let g be the cost of one gift
Write an inequality to represent the situation ( g + ) ge 70
Use the Distributive Property g + ge 70
Subtraction Property of Inequality g + 12 - ge 70 -
Simplify 8g ge
Division Property of Inequality 8g _
ge 58 _
Simplify g ge
Check your answer
Since g ge 725 check a larger number 8(8 + 150) ge 70
Sergio must spend at least on each gift ge 70
Reflect
3 Discussion Why is the first step in solving the inequality to use the Distributive Property instead of working inside the parentheses
Your Turn
4 Zachary is planning to send a video game to each of his two brothers If he buys the same game for both brothers and pays $475 to ship each game how much can he spend on each game without spending more than $100 Write and solve an inequality for this situation
Solve each inequality
5 4 _ 3 (6x + 9) lt 4 6 -2 ( 1 _ 4 x + 2 ) ge 5
Module 2 75 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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Explain 2 Creating and Solving Inequalities with Variables on Both Sides
Some inequalities have variable terms on both sides of the inequality symbol You can solve these inequalities the same way you solved equations with variables on both sides Use the properties of inequality to collect all the variable terms on one side and all the constant terms on the other side
Example 2
A The Daily Info charges a fee of $650 plus $80 per week to run an ad The Peoplersquos Paper charges $145 per week For how many weeks must an ad run for the total cost at the Daily Info to be less expensive than the cost at the Peoplersquos Paper Let w be the number of weeks the ad runs in the paper
Write an inequality to represent the situation 650 + 80w lt 145w
Subtraction Property of Inequality 650 + 80w - 80w lt 145w - 80w
Simplify 650 lt 65w
Division Property of Inequality 650 _ 65 lt 65w _ 65
Simplify 10 lt w
The total cost at the Daily Info is less than the cost at the Peoplersquos Paper if the ad runs for more than 10 weeks
B The Home Cleaning Company charges $312 to power-wash the siding of a house plus $12 for each window Power Clean charges $36 per window and the price includes power-washing the siding How many windows must a house have to make the total cost from The Home Cleaning Company less expensive than Power Clean Let w be the number of windows
Write an inequality to represent the situation +12w lt 36w
Subtraction Property of Inequality 312 + 12w - lt 36w -
Simplify 312 lt
Division Property of Inequality 312 _ lt 24w _
Simplify lt w
A house must have more than 13 windows for The Home Cleaning Company to be less expensive than Power Clean
Reflect
7 How would the final inequality change if you divided by ndash24 in the next to last step
Your Turn
8 The school band will sell pizzas to raise money for new uniforms The supplier charges $100 plus $4 per pizza The band members sell the pizzas for $7 each Write and solve an inequality to find how many pizzas the band members will have to sell to make a profit
Module 2 76 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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cour
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pan
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Elaborate
9 Which inequality symbol would you use to represent the following words or phrases Can you come up with more examples
a at most b farther than c younger than d up to
10 Discussion How are the steps to solving an inequality similar to those for solving an equation How are they different
11 Essential Question Check-In How can you write an inequality that represents a real-world situation
Write an inequality that represents the description and then solve
1 Max has more than 5 carrots (number of carrots Max has = c)
2 Brigitte is shorter than 5 feet (Brigittersquos height = h)
3 Twice a number (x) is less than 10 4 Six more than five times a number (x) is at least twenty-one
5 Dave has $15 to spend on an $8 book and two birthday cards (c) for his friends How much can he spend on each card if he buys the same card for each friend
6 Toni can carry up to 18 lb in her backpack Her lunch weighs 1 lb her gym clothes weigh 2 lb and her books (b) weigh 3 lb each How many books can she carry in her backpack
Evaluate Homework and Practice
bull Online Homeworkbull Hints and Helpbull Extra Practice
Module 2 77 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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oug
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arcourt Publishin
g Com
pany
Solve each inequality
7 3 (x - 2) gt -3 8 5 + 5 (x + 4) le 20 9 3 + 1 _ 2 (3 - x) lt -7
10 3 (x + 6) - 2 (x + 2) ge 10 11 5 (3 - x) -4 (2 - 3x) gt 2 12 1 _ 2 (4x - 2) - 2 _ 3 (6x + 9) le 4
13 x + 1 gt -5 (7 - 2x) 14 5 _ 3 (6x + 3) le 2x - 7
15 2x le - 2 __ 3 (4x + 4) 16 1 __ 2 (-2x - 10) gt 3 (4 - 6x)
17 -5 - 3x ge 2 (10 + 2x) + 3 18 -3 (9x + 20) ge 15x - 20
19 8 ( 1 _ 4 x - 3) + 24 lt 4 ( x + 5 ) 20 6x - 2 (x + 2) gt 2 - 3 (x + 3)
Module 2 78 Lesson 4
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21 Physics A crane cable can support a maximum load of 15000 kg If a bucket has a mass of 2000 kg and gravel has a mass of 1500 kg for every cubic meter how many cubic meters of gravel (g) can be safely lifted by the crane
22 Find the solution set of each inequality below and then determine which inequalities have the same solution set as 1 _ 3 ( -5x - 3 ) lt 14
a 1 _ 3 (5x + 3) gt -14 b 2 _ 5 (10x + 20) gt 44
c - 2 _ 5 (10x + 20) lt -44 d - 1 _ 3 (5x + 3) lt 14
e 2 _ 5 (10x - 20) gt -44 f 1 _ 3 (5x + 3) lt -14
HOT Focus on Higher Order Thinking
23 Explain the Error Sven is trying to find the maximum amount of time he can spend practicing the five scales of piano music he is supposed to be working on He has 60 minutes to practice piano and would like to spend at least 35 minutes playing songs instead of practicing scales So Sven sets up the following inequality where t is the number of minutes he spends on each scale and solves it
60 - 5t le 35-5t le -25
t ge 5
Sven has concluded that he should spend 5 minutes or more on each scale Is this correct If not what mistake did he make Then solve for the correct answer
Module 2 79 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
24 Critical Thinking Anika wants to determine the maximum number of tulip bulbs (t) she can purchase if each bulb costs $150 She will also need to purchase separate pots for each bulb at $125 each and a bag of potting soil for $1000 Set up an inequality to determine how many tulip bulbs Anika can purchase without spending more than $2000 and solve it Can Anika buy exactly enough bulbs and pots to spend the full $2000 Explain Can you think of a better inequality to describe the answer
25 Geometry The area of the triangle shown is no more than 10 square inches
a Write an inequality that can be used to find x
b Solve the inequality from part a c What is the maximum height of the triangle
Lesson Performance TaskWhen planning an airplane route the trip planner must be careful to consider the range the aircraft can travel and the availability of airports to stop and refuel
A large commercial jet airplane burns approximately 5 gallons of fuel per mile flown plus about 8500 gallons of fuel per trip to reach cruising altitude With a useable fuel capacity of 50000 gallons (there is additional fuel reserved for emergencies) describe the acceptable distance for which an airline could establish a non-stop flight
For flights originating from Chicago determine which cities could be safely reached by a non-stop flight
City Distance from Chicago (miles)
Bangalore India 8530
Jakarta Indonesia 9810
Johannesburg South Africa 8680
Moscow Russia 4970
Paris France 4130
Perth Australia 10970
Tokyo Japan 6300
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(2x - 3) in
4 in
Module 2 80 Lesson 4
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Name Class Date
Resource Locker
Explore Truth Tables and Compound StatementsA compound statement is formed by combining two or more simple statements A compound statement can be true or false A compound statement involving AND is true when both simple statements are true A compound statement involving OR is true when either one simple statement or both are true
A Complete the truth table
P QP
True or FalseQ
True or FalseP AND Q
True or False
A dog is a mammal Red is a color
A dog is a mammal Red is not a color
A dog is a fish Red is a color
A dog is a fish Red is not a color
B P AND Q is true when
C Complete the truth table
P QP
True or FalseQ
True or FalseP OR Q
True or False
1 is an odd number 2 is an even number
1 is an odd number 2 is an odd number
1 is an even number 2 is an even number
1 is an even number 2 is an odd number
D P OR Q is true when
Reflect
1 Give two simple statements P and Q for which P AND Q is false and P OR Q is true
Module 2 81 Lesson 5
25 Creating and Solving Compound Inequalities
Essential Question How can you solve a compound inequality and graph the solution set
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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Explain 1 Solving Compound Inequalities Involving ANDCombining two or more simple inequalities forms a compound inequality The graph of a compound inequality involving AND is the intersection or the overlapping region of the simple inequality graphs
Compound Inequalities AND
Words Algebra Graph
All real numbers greater than 2AND less than 6
x gt 2 AND x lt 62 lt x lt 6
All real numbers greater than or equal to 2 AND less than or equal to 6
x ge 2 AND x le 62 le x le 6
Example 1 Solve each compound inequality and graph the solutions
A 4 le x + 2 le 8
4 le x + 2 AND x + 2 le 8 Write the compound inequality using AND
4 - 2 le x + 2 - 2 x + 2 - 2 le 8 - 2 Subtract 2 from both sides of each simple inequality
2 le x x le 6 Simplify
Graph 2 le x
Graph x le 6
Graph the intersection by finding where the two graphs overlap
B -5 le 2x + 3 lt 9
-5 - le 2x + 3 - lt 9 - Subtract from each part of the inequality
le 2x lt Simplify
-8 _ le 2x _ lt 6 _ Divide each part of the inequality by
le x lt Simplify
Graph -4 le x
Graph x lt 3
Graph the intersection by finding where the two graphs overlap -1 0 1 2 3 4 5-5-4 -3 -2
0 2 4 6 8 10 12-8-6-4 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 82 Lesson 5
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Reflect
2 Discussion Explain why 2 le x le 6 can be considered the short method for writing the AND compound inequality x ge 2 AND x le 6
YourTurn
Solve each compound inequality and graph the solutions
3 -2 lt x - 3 lt 5
4 -10 lt 3x + 2 le 8
Explain 2 Solving Compound Inequalities Involving ORThe graph of a compound inequality involving OR is the union or the combined region of the simple inequality graphs
Compound Inequalities OR
Words Algebra Graph
All real numbers less than 2OR greater than 6
x lt 2 OR x gt 6
All real numbers less than or equal to 2OR greater than or equal to 6
x le 2 OR x ge 6
-1 0 1 2 3 4 5-5-4 -3 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 83 Lesson 5
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Example 2 Solve each compound inequality and graph the solutions
A -4 + x gt 1 OR -4 + x lt -3
-4 + x gt 1 OR -4 + x lt -3 Write the compound inequality using OR
-4 + 4 + x gt 1 + 4 -4 + 4 + x lt -3 + 4 Add 4 to both sides of each simple inequality
x gt 5 x lt 1 Simplify
Graph x gt 5
Graph x lt 1
Graph the union by combining the graphs
B 2x le 6 OR 3x gt 12
2x le 6 OR 3x gt 12 Write the compound inequality using OR
2x _ le 6 _ OR 3x _ gt 12 _ Divide the first simple inequality by
x le OR x gt
Graph x le 3
Graph x gt 4
Graph the union by combining the graphs
Reflect
5 Critical Thinking What kind of compound inequality has no solution
Divide the second simple inequality by
Simplify
0 1 2 3 4 5 6-4 -3 -2 -1
-0 1 2 3 4 5 6-4 -3 -2 -1
Module 2 84 Lesson 5
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Your Turn
Solve each compound inequality and graph the solutions
6 x - 5 ge -2 OR x -5 le -6
7 4x -1 lt 15 OR 8x ge 48
Explain 3 Creating Compound Inequalities From GraphsGiven a number line graph with a solution set graphed you can create a compound inequality to fit the graph
Example 3 Write the compound inequality shown by each graph
A
The shaded portion of the graph is not between two values so the compound inequality involves OR
On the left the graph shows an arrow pointing left from -1 and a solid circle so use le
The inequality is x le -1
On the right the graph shows an arrow pointing right from 7 and a solid circle so use ge
The inequality is x ge 7
The compound inequality is x le -1 OR x ge 7
B
The graph is shaded between the values and so the compound inequality involves AND
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The compound inequality is
-1 0 1 2 3 4 5-5-4 -3 -2
4 5 6 7 8 9 100 1 2 3
2 3 4 5 6 7 8-2 -1 0 1
10 2 3 4 5 6 7 8 9-1
Module 2 85 Lesson 5
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oug
hton Mifflin H
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Reflect
8 What is a short method to write the compound inequality x ge 0 AND x lt 6
Your Turn
Write the compound inequality shown by each graph
9
10
Explain 4 Expressing Acceptable Levels with Compound Inequalities
You can express quality-controls levels in real-world problems using compound inequalities
Example 4 Write a compound inequality to represent the indicated quality-control level and graph the solutions
A The recommended pH level for swimming pool water is between 72 and 76 inclusive
Let p be the pH level of swimming pool water
72 is less than or equal to pH level is less than or equal to 76
72 le p le 76
The compound inequality is 72 le p le 76
Graph the solutions
0-10 -8-9 -7-6 -5-4 -3 -2 -1
71 72 73 74 75 76 77 78 79 8070
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 86 Lesson 5
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oug
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B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
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oug
hton Mifflin H
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bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
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oug
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Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
arcourt Publishin
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pany bull Im
age C
redits copy
Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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bik
erid
erlo
nd
onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
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Explain 2 Rearranging Literal EquationsUsing inverse operations to rearrange literal equations can be applied to any formula The interest formula I = prt is another example of a literal equation In the formula I represents interest p the principal or the initial amount to which interest will be applied r the rate at which interest will be paid and t is the time in years
Example 2
A Find the number of years used in the calculation of a $1000 loan at an interest rate of 5 with interest totaling $600
Solve the formula for t
I = prt
I _ pr = prt
_ pr
I _ pr = t
Substitute the given values Since the interest rate is 5 r = 005$600 __
$1000 middot 005 = t
12 = t
So the length of time for the loan is 12 years
B Determine the interest rate for a $2000 loan that will be paid off in 4 years with interest totaling $640 In order to find the interest rate solve the formula for r
I = prt
I _ = prt _
_ = r
Now substitute the values and simplify
__
( ) ( ) = r
008 = r
So the interest rate is per year
Your Turn
3 The formula y = mx + b is the slope-intercept form of the equation of a line Solve the equation for m
Module 2 69 Lesson 3
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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oug
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bull Online Homeworkbull Hints and Helpbull Extra Practice
Solve for the indicated variable in each mathematical formula
1 C = 2πr for r 2 A = 1 __ 2 bh for b 3 y = mx + b for x
4 A = 1 __ 2 (a + b)h for h 5 V = πr2h for h 6 SA = 2πr2 + 2πrh for h
Solve for the indicated variable in each scientific formula
7 d = rt for t 8 PV = nRT for T
9 A = FV - OV _______ T for OV 10 C = Wtc _ 1000 for W
Evaluate Homework and Practice
Elaborate
4 Discussion What could be a reason for isolating a variable in a literal equation
5 Describe a situation in which a formula could be used more easily if it were rearranged Include the formula in your description
6 Essential Question Check-In How do you isolate a variable
Module 2 70 Lesson 3
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copyO
cean
C
orb
is
Solve for the indicated variable in each literal equation
11 2p + 5r = q for p 12 -10 = xy + z for x 13 a __ b = c for b
14 h - 4 _ j = k for j 15 x __ 5 - g = a for x 16 5p + 9c = p for c
17 2 __ 5 (z + 1) = y for z 18 g (h + 2 __ 3 ) = 1 for h 19 a(n - 3) + 8 = bn for n
20 Which is a possible way to rewrite the equation y = 3x + 3b to solve for b
A b = y - 3x
_ 3 C b = y - 3
_____ 3x
B b = 3(y - 3x) D b = x(y - 3)
21 Sports To find a baseball pitcherrsquos earned run average (ERA) you can use the formula Ei = 9r in which E represents ERA i represents the number of innings pitched and r represents the number of earned runs allowed Solve the equation for E What is a pitcherrsquos ERA if he allows 5 earned runs in 18 innings pitched
22 Meteorology For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Solve the equation for a If the atmospheric temperature is -655 ∘F and the ground temperature is 57 ∘F what is the altitude
Module 2 71 Lesson 3
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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Rand
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HOT Focus on Higher Order Thinking
23 Explain the Error A student was asked to use the formula for the perimeter of a rectangle P = 2ℓ + 2w to solve for ℓ The student came up with an answer P - 2w = 2ℓ What error did the student make Explain Then solve for ℓ
24 Multi-Step The formula c = 5p + 215 relates c the total cost in dollars of hosting a birthday party at a skating rink to p the number of people attending If Alliersquos parents are willing to spend $300 for a party how many people can attend
25 Multi-Step The formula for the area of a triangle is A = 1 __ 2 bh in which b represents the length of thebase and h represents the height If a triangle has an area of 192 mm2 and the height is 12 mm what is the measure of the base
Lesson Performance TaskThe following table shows the average low temperatures in Fahrenheit for the city of Boston for several months during the year The formula F = 9 __ 5 C + 32 allows you to determine the temperature in Fahrenheit when given the temperature in Celsius
MonthTemperature in
FahrenheitTemperature in
Celsius
January 22deg
April 41deg
July 65deg
October 47deg
December 28deg
a Use the information given to determine the average low temperatures in Celsius
b Would it ever be possible for the temperature in Celsius to have a greater value than the temperature in Fahrenheit Explain why or why not
Module 2 72 Lesson 3
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
Name Class Date
Resource Locker
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oug
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e cr
edit
s copy
Patr
ick
Lan
eSo
mos
Imag
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orb
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Explore Creating Inequalities from Verbal DescriptionsAn inequality is a statement that compares two expressions that are not strictly equal by using one of the following inequality signs
Symbol Meaning
lt is less than
le is less than or equal to
gt is greater than
ge is greater than or equal to
ne is not equal to
You have probably seen a sign at an amusement park saying something like ldquoYou must be at least 48 inches tall to ride this riderdquo This statement could be written as h ge 48 in where h represents the height of a person allowed to ride
Nora is planning a birthday party for her little sister Colleen Norarsquos budget will allow her to spend no more than $50 for party supplies Eight children including Colleen will attend the party and Nora wants to determine how much she could spend on party favors for each child She will also purchase a cake for $10 Write an inequality that represents the situation and find possible solutions
A First let c represent the cost of a party favor for each child Write an expression for the total cost of the party as a function of c
c +
B Which inequality symbol should be used to represent the phrase ldquono more thanrdquo
C Write the inequality that represents Norarsquos budget goal
8c + 10 le
D Suppose Nora finds party favors that cost $4 each Use a value of 4 for c and check to see if this inequality is true
8 middot 4 + 10 le 50
le 50
Module 2 73 Lesson 4
24 Creating and Solving Inequalities
Essential Question How do you write and solve an inequality that represents a real-world situation
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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Is the inequality true
Could Nora buy $6 party favors for all of her guests without going over budget
Reflect
1 Why does an inequality represent Norarsquos budget calculation better than an equation
2 The solution set of an inequality consists of all values that make the statement true Describe the whole dollar amounts that are in the solution set for this situation
Explain 1 Creating and Solving Inequalities Involving the Distributive Property
You may need to use the Distributive Property before you can solve an inequality
Distributive Property If a b and c are real numbers then a(b + c) = ab + ac
The inequality sign must be reversed when multiplying or dividing both sides of an inequality by a negative number
Example 1
A Trina is buying 12 shirts for the drama club She will choose a style for the blank shirts and then pay an additional charge of $275 for each shirt to have the club logo If Trina cannot spend more than $99 how much can she spend on each blank shirt Write and solve an inequality to find the possible cost of each blank shirt
Let s represent the cost of each blank shirt
Write an inequality to represent the situation 12(s + 275) le 99
Use the Distributive Property 12s + 33 le 99
Subtraction Property of Inequality 12s + 33 - 33 le 99 - 33
Simplify 12s le 66
Division Property of Inequality 12s ___ 12 le 66 __ 12
Simplify s le 55
Module 2 74 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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pan
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Check your answer
Since s le 55 check a smaller number 12(5 + 275) le 99
Trina can order blank shirts that cost $550 or less 93 le 99 true
B Sergio needs to buy gifts for 8 friends He wants to give the same gift to all his friends and he plans to have the gifts wrapped for an additional charge of $150 each If Sergio spends at least $70 he will receive free shipping on his order Write and solve an inequality to determine how much Sergio needs to spend on each gift in order to receive free shipping
Let g be the cost of one gift
Write an inequality to represent the situation ( g + ) ge 70
Use the Distributive Property g + ge 70
Subtraction Property of Inequality g + 12 - ge 70 -
Simplify 8g ge
Division Property of Inequality 8g _
ge 58 _
Simplify g ge
Check your answer
Since g ge 725 check a larger number 8(8 + 150) ge 70
Sergio must spend at least on each gift ge 70
Reflect
3 Discussion Why is the first step in solving the inequality to use the Distributive Property instead of working inside the parentheses
Your Turn
4 Zachary is planning to send a video game to each of his two brothers If he buys the same game for both brothers and pays $475 to ship each game how much can he spend on each game without spending more than $100 Write and solve an inequality for this situation
Solve each inequality
5 4 _ 3 (6x + 9) lt 4 6 -2 ( 1 _ 4 x + 2 ) ge 5
Module 2 75 Lesson 4
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Explain 2 Creating and Solving Inequalities with Variables on Both Sides
Some inequalities have variable terms on both sides of the inequality symbol You can solve these inequalities the same way you solved equations with variables on both sides Use the properties of inequality to collect all the variable terms on one side and all the constant terms on the other side
Example 2
A The Daily Info charges a fee of $650 plus $80 per week to run an ad The Peoplersquos Paper charges $145 per week For how many weeks must an ad run for the total cost at the Daily Info to be less expensive than the cost at the Peoplersquos Paper Let w be the number of weeks the ad runs in the paper
Write an inequality to represent the situation 650 + 80w lt 145w
Subtraction Property of Inequality 650 + 80w - 80w lt 145w - 80w
Simplify 650 lt 65w
Division Property of Inequality 650 _ 65 lt 65w _ 65
Simplify 10 lt w
The total cost at the Daily Info is less than the cost at the Peoplersquos Paper if the ad runs for more than 10 weeks
B The Home Cleaning Company charges $312 to power-wash the siding of a house plus $12 for each window Power Clean charges $36 per window and the price includes power-washing the siding How many windows must a house have to make the total cost from The Home Cleaning Company less expensive than Power Clean Let w be the number of windows
Write an inequality to represent the situation +12w lt 36w
Subtraction Property of Inequality 312 + 12w - lt 36w -
Simplify 312 lt
Division Property of Inequality 312 _ lt 24w _
Simplify lt w
A house must have more than 13 windows for The Home Cleaning Company to be less expensive than Power Clean
Reflect
7 How would the final inequality change if you divided by ndash24 in the next to last step
Your Turn
8 The school band will sell pizzas to raise money for new uniforms The supplier charges $100 plus $4 per pizza The band members sell the pizzas for $7 each Write and solve an inequality to find how many pizzas the band members will have to sell to make a profit
Module 2 76 Lesson 4
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Elaborate
9 Which inequality symbol would you use to represent the following words or phrases Can you come up with more examples
a at most b farther than c younger than d up to
10 Discussion How are the steps to solving an inequality similar to those for solving an equation How are they different
11 Essential Question Check-In How can you write an inequality that represents a real-world situation
Write an inequality that represents the description and then solve
1 Max has more than 5 carrots (number of carrots Max has = c)
2 Brigitte is shorter than 5 feet (Brigittersquos height = h)
3 Twice a number (x) is less than 10 4 Six more than five times a number (x) is at least twenty-one
5 Dave has $15 to spend on an $8 book and two birthday cards (c) for his friends How much can he spend on each card if he buys the same card for each friend
6 Toni can carry up to 18 lb in her backpack Her lunch weighs 1 lb her gym clothes weigh 2 lb and her books (b) weigh 3 lb each How many books can she carry in her backpack
Evaluate Homework and Practice
bull Online Homeworkbull Hints and Helpbull Extra Practice
Module 2 77 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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pany
Solve each inequality
7 3 (x - 2) gt -3 8 5 + 5 (x + 4) le 20 9 3 + 1 _ 2 (3 - x) lt -7
10 3 (x + 6) - 2 (x + 2) ge 10 11 5 (3 - x) -4 (2 - 3x) gt 2 12 1 _ 2 (4x - 2) - 2 _ 3 (6x + 9) le 4
13 x + 1 gt -5 (7 - 2x) 14 5 _ 3 (6x + 3) le 2x - 7
15 2x le - 2 __ 3 (4x + 4) 16 1 __ 2 (-2x - 10) gt 3 (4 - 6x)
17 -5 - 3x ge 2 (10 + 2x) + 3 18 -3 (9x + 20) ge 15x - 20
19 8 ( 1 _ 4 x - 3) + 24 lt 4 ( x + 5 ) 20 6x - 2 (x + 2) gt 2 - 3 (x + 3)
Module 2 78 Lesson 4
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21 Physics A crane cable can support a maximum load of 15000 kg If a bucket has a mass of 2000 kg and gravel has a mass of 1500 kg for every cubic meter how many cubic meters of gravel (g) can be safely lifted by the crane
22 Find the solution set of each inequality below and then determine which inequalities have the same solution set as 1 _ 3 ( -5x - 3 ) lt 14
a 1 _ 3 (5x + 3) gt -14 b 2 _ 5 (10x + 20) gt 44
c - 2 _ 5 (10x + 20) lt -44 d - 1 _ 3 (5x + 3) lt 14
e 2 _ 5 (10x - 20) gt -44 f 1 _ 3 (5x + 3) lt -14
HOT Focus on Higher Order Thinking
23 Explain the Error Sven is trying to find the maximum amount of time he can spend practicing the five scales of piano music he is supposed to be working on He has 60 minutes to practice piano and would like to spend at least 35 minutes playing songs instead of practicing scales So Sven sets up the following inequality where t is the number of minutes he spends on each scale and solves it
60 - 5t le 35-5t le -25
t ge 5
Sven has concluded that he should spend 5 minutes or more on each scale Is this correct If not what mistake did he make Then solve for the correct answer
Module 2 79 Lesson 4
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24 Critical Thinking Anika wants to determine the maximum number of tulip bulbs (t) she can purchase if each bulb costs $150 She will also need to purchase separate pots for each bulb at $125 each and a bag of potting soil for $1000 Set up an inequality to determine how many tulip bulbs Anika can purchase without spending more than $2000 and solve it Can Anika buy exactly enough bulbs and pots to spend the full $2000 Explain Can you think of a better inequality to describe the answer
25 Geometry The area of the triangle shown is no more than 10 square inches
a Write an inequality that can be used to find x
b Solve the inequality from part a c What is the maximum height of the triangle
Lesson Performance TaskWhen planning an airplane route the trip planner must be careful to consider the range the aircraft can travel and the availability of airports to stop and refuel
A large commercial jet airplane burns approximately 5 gallons of fuel per mile flown plus about 8500 gallons of fuel per trip to reach cruising altitude With a useable fuel capacity of 50000 gallons (there is additional fuel reserved for emergencies) describe the acceptable distance for which an airline could establish a non-stop flight
For flights originating from Chicago determine which cities could be safely reached by a non-stop flight
City Distance from Chicago (miles)
Bangalore India 8530
Jakarta Indonesia 9810
Johannesburg South Africa 8680
Moscow Russia 4970
Paris France 4130
Perth Australia 10970
Tokyo Japan 6300
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oug
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eva O
lesiaShutterstock
(2x - 3) in
4 in
Module 2 80 Lesson 4
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Name Class Date
Resource Locker
Explore Truth Tables and Compound StatementsA compound statement is formed by combining two or more simple statements A compound statement can be true or false A compound statement involving AND is true when both simple statements are true A compound statement involving OR is true when either one simple statement or both are true
A Complete the truth table
P QP
True or FalseQ
True or FalseP AND Q
True or False
A dog is a mammal Red is a color
A dog is a mammal Red is not a color
A dog is a fish Red is a color
A dog is a fish Red is not a color
B P AND Q is true when
C Complete the truth table
P QP
True or FalseQ
True or FalseP OR Q
True or False
1 is an odd number 2 is an even number
1 is an odd number 2 is an odd number
1 is an even number 2 is an even number
1 is an even number 2 is an odd number
D P OR Q is true when
Reflect
1 Give two simple statements P and Q for which P AND Q is false and P OR Q is true
Module 2 81 Lesson 5
25 Creating and Solving Compound Inequalities
Essential Question How can you solve a compound inequality and graph the solution set
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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Explain 1 Solving Compound Inequalities Involving ANDCombining two or more simple inequalities forms a compound inequality The graph of a compound inequality involving AND is the intersection or the overlapping region of the simple inequality graphs
Compound Inequalities AND
Words Algebra Graph
All real numbers greater than 2AND less than 6
x gt 2 AND x lt 62 lt x lt 6
All real numbers greater than or equal to 2 AND less than or equal to 6
x ge 2 AND x le 62 le x le 6
Example 1 Solve each compound inequality and graph the solutions
A 4 le x + 2 le 8
4 le x + 2 AND x + 2 le 8 Write the compound inequality using AND
4 - 2 le x + 2 - 2 x + 2 - 2 le 8 - 2 Subtract 2 from both sides of each simple inequality
2 le x x le 6 Simplify
Graph 2 le x
Graph x le 6
Graph the intersection by finding where the two graphs overlap
B -5 le 2x + 3 lt 9
-5 - le 2x + 3 - lt 9 - Subtract from each part of the inequality
le 2x lt Simplify
-8 _ le 2x _ lt 6 _ Divide each part of the inequality by
le x lt Simplify
Graph -4 le x
Graph x lt 3
Graph the intersection by finding where the two graphs overlap -1 0 1 2 3 4 5-5-4 -3 -2
0 2 4 6 8 10 12-8-6-4 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 82 Lesson 5
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Reflect
2 Discussion Explain why 2 le x le 6 can be considered the short method for writing the AND compound inequality x ge 2 AND x le 6
YourTurn
Solve each compound inequality and graph the solutions
3 -2 lt x - 3 lt 5
4 -10 lt 3x + 2 le 8
Explain 2 Solving Compound Inequalities Involving ORThe graph of a compound inequality involving OR is the union or the combined region of the simple inequality graphs
Compound Inequalities OR
Words Algebra Graph
All real numbers less than 2OR greater than 6
x lt 2 OR x gt 6
All real numbers less than or equal to 2OR greater than or equal to 6
x le 2 OR x ge 6
-1 0 1 2 3 4 5-5-4 -3 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 83 Lesson 5
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Example 2 Solve each compound inequality and graph the solutions
A -4 + x gt 1 OR -4 + x lt -3
-4 + x gt 1 OR -4 + x lt -3 Write the compound inequality using OR
-4 + 4 + x gt 1 + 4 -4 + 4 + x lt -3 + 4 Add 4 to both sides of each simple inequality
x gt 5 x lt 1 Simplify
Graph x gt 5
Graph x lt 1
Graph the union by combining the graphs
B 2x le 6 OR 3x gt 12
2x le 6 OR 3x gt 12 Write the compound inequality using OR
2x _ le 6 _ OR 3x _ gt 12 _ Divide the first simple inequality by
x le OR x gt
Graph x le 3
Graph x gt 4
Graph the union by combining the graphs
Reflect
5 Critical Thinking What kind of compound inequality has no solution
Divide the second simple inequality by
Simplify
0 1 2 3 4 5 6-4 -3 -2 -1
-0 1 2 3 4 5 6-4 -3 -2 -1
Module 2 84 Lesson 5
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Your Turn
Solve each compound inequality and graph the solutions
6 x - 5 ge -2 OR x -5 le -6
7 4x -1 lt 15 OR 8x ge 48
Explain 3 Creating Compound Inequalities From GraphsGiven a number line graph with a solution set graphed you can create a compound inequality to fit the graph
Example 3 Write the compound inequality shown by each graph
A
The shaded portion of the graph is not between two values so the compound inequality involves OR
On the left the graph shows an arrow pointing left from -1 and a solid circle so use le
The inequality is x le -1
On the right the graph shows an arrow pointing right from 7 and a solid circle so use ge
The inequality is x ge 7
The compound inequality is x le -1 OR x ge 7
B
The graph is shaded between the values and so the compound inequality involves AND
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The compound inequality is
-1 0 1 2 3 4 5-5-4 -3 -2
4 5 6 7 8 9 100 1 2 3
2 3 4 5 6 7 8-2 -1 0 1
10 2 3 4 5 6 7 8 9-1
Module 2 85 Lesson 5
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oug
hton Mifflin H
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Reflect
8 What is a short method to write the compound inequality x ge 0 AND x lt 6
Your Turn
Write the compound inequality shown by each graph
9
10
Explain 4 Expressing Acceptable Levels with Compound Inequalities
You can express quality-controls levels in real-world problems using compound inequalities
Example 4 Write a compound inequality to represent the indicated quality-control level and graph the solutions
A The recommended pH level for swimming pool water is between 72 and 76 inclusive
Let p be the pH level of swimming pool water
72 is less than or equal to pH level is less than or equal to 76
72 le p le 76
The compound inequality is 72 le p le 76
Graph the solutions
0-10 -8-9 -7-6 -5-4 -3 -2 -1
71 72 73 74 75 76 77 78 79 8070
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 86 Lesson 5
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oug
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B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
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oug
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bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
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Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
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redits copy
Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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bik
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onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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pany
bull Online Homeworkbull Hints and Helpbull Extra Practice
Solve for the indicated variable in each mathematical formula
1 C = 2πr for r 2 A = 1 __ 2 bh for b 3 y = mx + b for x
4 A = 1 __ 2 (a + b)h for h 5 V = πr2h for h 6 SA = 2πr2 + 2πrh for h
Solve for the indicated variable in each scientific formula
7 d = rt for t 8 PV = nRT for T
9 A = FV - OV _______ T for OV 10 C = Wtc _ 1000 for W
Evaluate Homework and Practice
Elaborate
4 Discussion What could be a reason for isolating a variable in a literal equation
5 Describe a situation in which a formula could be used more easily if it were rearranged Include the formula in your description
6 Essential Question Check-In How do you isolate a variable
Module 2 70 Lesson 3
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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copyO
cean
C
orb
is
Solve for the indicated variable in each literal equation
11 2p + 5r = q for p 12 -10 = xy + z for x 13 a __ b = c for b
14 h - 4 _ j = k for j 15 x __ 5 - g = a for x 16 5p + 9c = p for c
17 2 __ 5 (z + 1) = y for z 18 g (h + 2 __ 3 ) = 1 for h 19 a(n - 3) + 8 = bn for n
20 Which is a possible way to rewrite the equation y = 3x + 3b to solve for b
A b = y - 3x
_ 3 C b = y - 3
_____ 3x
B b = 3(y - 3x) D b = x(y - 3)
21 Sports To find a baseball pitcherrsquos earned run average (ERA) you can use the formula Ei = 9r in which E represents ERA i represents the number of innings pitched and r represents the number of earned runs allowed Solve the equation for E What is a pitcherrsquos ERA if he allows 5 earned runs in 18 innings pitched
22 Meteorology For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Solve the equation for a If the atmospheric temperature is -655 ∘F and the ground temperature is 57 ∘F what is the altitude
Module 2 71 Lesson 3
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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Rand
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aineA
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HOT Focus on Higher Order Thinking
23 Explain the Error A student was asked to use the formula for the perimeter of a rectangle P = 2ℓ + 2w to solve for ℓ The student came up with an answer P - 2w = 2ℓ What error did the student make Explain Then solve for ℓ
24 Multi-Step The formula c = 5p + 215 relates c the total cost in dollars of hosting a birthday party at a skating rink to p the number of people attending If Alliersquos parents are willing to spend $300 for a party how many people can attend
25 Multi-Step The formula for the area of a triangle is A = 1 __ 2 bh in which b represents the length of thebase and h represents the height If a triangle has an area of 192 mm2 and the height is 12 mm what is the measure of the base
Lesson Performance TaskThe following table shows the average low temperatures in Fahrenheit for the city of Boston for several months during the year The formula F = 9 __ 5 C + 32 allows you to determine the temperature in Fahrenheit when given the temperature in Celsius
MonthTemperature in
FahrenheitTemperature in
Celsius
January 22deg
April 41deg
July 65deg
October 47deg
December 28deg
a Use the information given to determine the average low temperatures in Celsius
b Would it ever be possible for the temperature in Celsius to have a greater value than the temperature in Fahrenheit Explain why or why not
Module 2 72 Lesson 3
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
Name Class Date
Resource Locker
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edit
s copy
Patr
ick
Lan
eSo
mos
Imag
esC
orb
is
Explore Creating Inequalities from Verbal DescriptionsAn inequality is a statement that compares two expressions that are not strictly equal by using one of the following inequality signs
Symbol Meaning
lt is less than
le is less than or equal to
gt is greater than
ge is greater than or equal to
ne is not equal to
You have probably seen a sign at an amusement park saying something like ldquoYou must be at least 48 inches tall to ride this riderdquo This statement could be written as h ge 48 in where h represents the height of a person allowed to ride
Nora is planning a birthday party for her little sister Colleen Norarsquos budget will allow her to spend no more than $50 for party supplies Eight children including Colleen will attend the party and Nora wants to determine how much she could spend on party favors for each child She will also purchase a cake for $10 Write an inequality that represents the situation and find possible solutions
A First let c represent the cost of a party favor for each child Write an expression for the total cost of the party as a function of c
c +
B Which inequality symbol should be used to represent the phrase ldquono more thanrdquo
C Write the inequality that represents Norarsquos budget goal
8c + 10 le
D Suppose Nora finds party favors that cost $4 each Use a value of 4 for c and check to see if this inequality is true
8 middot 4 + 10 le 50
le 50
Module 2 73 Lesson 4
24 Creating and Solving Inequalities
Essential Question How do you write and solve an inequality that represents a real-world situation
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
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pany
Is the inequality true
Could Nora buy $6 party favors for all of her guests without going over budget
Reflect
1 Why does an inequality represent Norarsquos budget calculation better than an equation
2 The solution set of an inequality consists of all values that make the statement true Describe the whole dollar amounts that are in the solution set for this situation
Explain 1 Creating and Solving Inequalities Involving the Distributive Property
You may need to use the Distributive Property before you can solve an inequality
Distributive Property If a b and c are real numbers then a(b + c) = ab + ac
The inequality sign must be reversed when multiplying or dividing both sides of an inequality by a negative number
Example 1
A Trina is buying 12 shirts for the drama club She will choose a style for the blank shirts and then pay an additional charge of $275 for each shirt to have the club logo If Trina cannot spend more than $99 how much can she spend on each blank shirt Write and solve an inequality to find the possible cost of each blank shirt
Let s represent the cost of each blank shirt
Write an inequality to represent the situation 12(s + 275) le 99
Use the Distributive Property 12s + 33 le 99
Subtraction Property of Inequality 12s + 33 - 33 le 99 - 33
Simplify 12s le 66
Division Property of Inequality 12s ___ 12 le 66 __ 12
Simplify s le 55
Module 2 74 Lesson 4
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pan
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Check your answer
Since s le 55 check a smaller number 12(5 + 275) le 99
Trina can order blank shirts that cost $550 or less 93 le 99 true
B Sergio needs to buy gifts for 8 friends He wants to give the same gift to all his friends and he plans to have the gifts wrapped for an additional charge of $150 each If Sergio spends at least $70 he will receive free shipping on his order Write and solve an inequality to determine how much Sergio needs to spend on each gift in order to receive free shipping
Let g be the cost of one gift
Write an inequality to represent the situation ( g + ) ge 70
Use the Distributive Property g + ge 70
Subtraction Property of Inequality g + 12 - ge 70 -
Simplify 8g ge
Division Property of Inequality 8g _
ge 58 _
Simplify g ge
Check your answer
Since g ge 725 check a larger number 8(8 + 150) ge 70
Sergio must spend at least on each gift ge 70
Reflect
3 Discussion Why is the first step in solving the inequality to use the Distributive Property instead of working inside the parentheses
Your Turn
4 Zachary is planning to send a video game to each of his two brothers If he buys the same game for both brothers and pays $475 to ship each game how much can he spend on each game without spending more than $100 Write and solve an inequality for this situation
Solve each inequality
5 4 _ 3 (6x + 9) lt 4 6 -2 ( 1 _ 4 x + 2 ) ge 5
Module 2 75 Lesson 4
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Explain 2 Creating and Solving Inequalities with Variables on Both Sides
Some inequalities have variable terms on both sides of the inequality symbol You can solve these inequalities the same way you solved equations with variables on both sides Use the properties of inequality to collect all the variable terms on one side and all the constant terms on the other side
Example 2
A The Daily Info charges a fee of $650 plus $80 per week to run an ad The Peoplersquos Paper charges $145 per week For how many weeks must an ad run for the total cost at the Daily Info to be less expensive than the cost at the Peoplersquos Paper Let w be the number of weeks the ad runs in the paper
Write an inequality to represent the situation 650 + 80w lt 145w
Subtraction Property of Inequality 650 + 80w - 80w lt 145w - 80w
Simplify 650 lt 65w
Division Property of Inequality 650 _ 65 lt 65w _ 65
Simplify 10 lt w
The total cost at the Daily Info is less than the cost at the Peoplersquos Paper if the ad runs for more than 10 weeks
B The Home Cleaning Company charges $312 to power-wash the siding of a house plus $12 for each window Power Clean charges $36 per window and the price includes power-washing the siding How many windows must a house have to make the total cost from The Home Cleaning Company less expensive than Power Clean Let w be the number of windows
Write an inequality to represent the situation +12w lt 36w
Subtraction Property of Inequality 312 + 12w - lt 36w -
Simplify 312 lt
Division Property of Inequality 312 _ lt 24w _
Simplify lt w
A house must have more than 13 windows for The Home Cleaning Company to be less expensive than Power Clean
Reflect
7 How would the final inequality change if you divided by ndash24 in the next to last step
Your Turn
8 The school band will sell pizzas to raise money for new uniforms The supplier charges $100 plus $4 per pizza The band members sell the pizzas for $7 each Write and solve an inequality to find how many pizzas the band members will have to sell to make a profit
Module 2 76 Lesson 4
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Elaborate
9 Which inequality symbol would you use to represent the following words or phrases Can you come up with more examples
a at most b farther than c younger than d up to
10 Discussion How are the steps to solving an inequality similar to those for solving an equation How are they different
11 Essential Question Check-In How can you write an inequality that represents a real-world situation
Write an inequality that represents the description and then solve
1 Max has more than 5 carrots (number of carrots Max has = c)
2 Brigitte is shorter than 5 feet (Brigittersquos height = h)
3 Twice a number (x) is less than 10 4 Six more than five times a number (x) is at least twenty-one
5 Dave has $15 to spend on an $8 book and two birthday cards (c) for his friends How much can he spend on each card if he buys the same card for each friend
6 Toni can carry up to 18 lb in her backpack Her lunch weighs 1 lb her gym clothes weigh 2 lb and her books (b) weigh 3 lb each How many books can she carry in her backpack
Evaluate Homework and Practice
bull Online Homeworkbull Hints and Helpbull Extra Practice
Module 2 77 Lesson 4
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Solve each inequality
7 3 (x - 2) gt -3 8 5 + 5 (x + 4) le 20 9 3 + 1 _ 2 (3 - x) lt -7
10 3 (x + 6) - 2 (x + 2) ge 10 11 5 (3 - x) -4 (2 - 3x) gt 2 12 1 _ 2 (4x - 2) - 2 _ 3 (6x + 9) le 4
13 x + 1 gt -5 (7 - 2x) 14 5 _ 3 (6x + 3) le 2x - 7
15 2x le - 2 __ 3 (4x + 4) 16 1 __ 2 (-2x - 10) gt 3 (4 - 6x)
17 -5 - 3x ge 2 (10 + 2x) + 3 18 -3 (9x + 20) ge 15x - 20
19 8 ( 1 _ 4 x - 3) + 24 lt 4 ( x + 5 ) 20 6x - 2 (x + 2) gt 2 - 3 (x + 3)
Module 2 78 Lesson 4
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21 Physics A crane cable can support a maximum load of 15000 kg If a bucket has a mass of 2000 kg and gravel has a mass of 1500 kg for every cubic meter how many cubic meters of gravel (g) can be safely lifted by the crane
22 Find the solution set of each inequality below and then determine which inequalities have the same solution set as 1 _ 3 ( -5x - 3 ) lt 14
a 1 _ 3 (5x + 3) gt -14 b 2 _ 5 (10x + 20) gt 44
c - 2 _ 5 (10x + 20) lt -44 d - 1 _ 3 (5x + 3) lt 14
e 2 _ 5 (10x - 20) gt -44 f 1 _ 3 (5x + 3) lt -14
HOT Focus on Higher Order Thinking
23 Explain the Error Sven is trying to find the maximum amount of time he can spend practicing the five scales of piano music he is supposed to be working on He has 60 minutes to practice piano and would like to spend at least 35 minutes playing songs instead of practicing scales So Sven sets up the following inequality where t is the number of minutes he spends on each scale and solves it
60 - 5t le 35-5t le -25
t ge 5
Sven has concluded that he should spend 5 minutes or more on each scale Is this correct If not what mistake did he make Then solve for the correct answer
Module 2 79 Lesson 4
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24 Critical Thinking Anika wants to determine the maximum number of tulip bulbs (t) she can purchase if each bulb costs $150 She will also need to purchase separate pots for each bulb at $125 each and a bag of potting soil for $1000 Set up an inequality to determine how many tulip bulbs Anika can purchase without spending more than $2000 and solve it Can Anika buy exactly enough bulbs and pots to spend the full $2000 Explain Can you think of a better inequality to describe the answer
25 Geometry The area of the triangle shown is no more than 10 square inches
a Write an inequality that can be used to find x
b Solve the inequality from part a c What is the maximum height of the triangle
Lesson Performance TaskWhen planning an airplane route the trip planner must be careful to consider the range the aircraft can travel and the availability of airports to stop and refuel
A large commercial jet airplane burns approximately 5 gallons of fuel per mile flown plus about 8500 gallons of fuel per trip to reach cruising altitude With a useable fuel capacity of 50000 gallons (there is additional fuel reserved for emergencies) describe the acceptable distance for which an airline could establish a non-stop flight
For flights originating from Chicago determine which cities could be safely reached by a non-stop flight
City Distance from Chicago (miles)
Bangalore India 8530
Jakarta Indonesia 9810
Johannesburg South Africa 8680
Moscow Russia 4970
Paris France 4130
Perth Australia 10970
Tokyo Japan 6300
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eva O
lesiaShutterstock
(2x - 3) in
4 in
Module 2 80 Lesson 4
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Name Class Date
Resource Locker
Explore Truth Tables and Compound StatementsA compound statement is formed by combining two or more simple statements A compound statement can be true or false A compound statement involving AND is true when both simple statements are true A compound statement involving OR is true when either one simple statement or both are true
A Complete the truth table
P QP
True or FalseQ
True or FalseP AND Q
True or False
A dog is a mammal Red is a color
A dog is a mammal Red is not a color
A dog is a fish Red is a color
A dog is a fish Red is not a color
B P AND Q is true when
C Complete the truth table
P QP
True or FalseQ
True or FalseP OR Q
True or False
1 is an odd number 2 is an even number
1 is an odd number 2 is an odd number
1 is an even number 2 is an even number
1 is an even number 2 is an odd number
D P OR Q is true when
Reflect
1 Give two simple statements P and Q for which P AND Q is false and P OR Q is true
Module 2 81 Lesson 5
25 Creating and Solving Compound Inequalities
Essential Question How can you solve a compound inequality and graph the solution set
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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Explain 1 Solving Compound Inequalities Involving ANDCombining two or more simple inequalities forms a compound inequality The graph of a compound inequality involving AND is the intersection or the overlapping region of the simple inequality graphs
Compound Inequalities AND
Words Algebra Graph
All real numbers greater than 2AND less than 6
x gt 2 AND x lt 62 lt x lt 6
All real numbers greater than or equal to 2 AND less than or equal to 6
x ge 2 AND x le 62 le x le 6
Example 1 Solve each compound inequality and graph the solutions
A 4 le x + 2 le 8
4 le x + 2 AND x + 2 le 8 Write the compound inequality using AND
4 - 2 le x + 2 - 2 x + 2 - 2 le 8 - 2 Subtract 2 from both sides of each simple inequality
2 le x x le 6 Simplify
Graph 2 le x
Graph x le 6
Graph the intersection by finding where the two graphs overlap
B -5 le 2x + 3 lt 9
-5 - le 2x + 3 - lt 9 - Subtract from each part of the inequality
le 2x lt Simplify
-8 _ le 2x _ lt 6 _ Divide each part of the inequality by
le x lt Simplify
Graph -4 le x
Graph x lt 3
Graph the intersection by finding where the two graphs overlap -1 0 1 2 3 4 5-5-4 -3 -2
0 2 4 6 8 10 12-8-6-4 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 82 Lesson 5
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Reflect
2 Discussion Explain why 2 le x le 6 can be considered the short method for writing the AND compound inequality x ge 2 AND x le 6
YourTurn
Solve each compound inequality and graph the solutions
3 -2 lt x - 3 lt 5
4 -10 lt 3x + 2 le 8
Explain 2 Solving Compound Inequalities Involving ORThe graph of a compound inequality involving OR is the union or the combined region of the simple inequality graphs
Compound Inequalities OR
Words Algebra Graph
All real numbers less than 2OR greater than 6
x lt 2 OR x gt 6
All real numbers less than or equal to 2OR greater than or equal to 6
x le 2 OR x ge 6
-1 0 1 2 3 4 5-5-4 -3 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 83 Lesson 5
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Example 2 Solve each compound inequality and graph the solutions
A -4 + x gt 1 OR -4 + x lt -3
-4 + x gt 1 OR -4 + x lt -3 Write the compound inequality using OR
-4 + 4 + x gt 1 + 4 -4 + 4 + x lt -3 + 4 Add 4 to both sides of each simple inequality
x gt 5 x lt 1 Simplify
Graph x gt 5
Graph x lt 1
Graph the union by combining the graphs
B 2x le 6 OR 3x gt 12
2x le 6 OR 3x gt 12 Write the compound inequality using OR
2x _ le 6 _ OR 3x _ gt 12 _ Divide the first simple inequality by
x le OR x gt
Graph x le 3
Graph x gt 4
Graph the union by combining the graphs
Reflect
5 Critical Thinking What kind of compound inequality has no solution
Divide the second simple inequality by
Simplify
0 1 2 3 4 5 6-4 -3 -2 -1
-0 1 2 3 4 5 6-4 -3 -2 -1
Module 2 84 Lesson 5
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Your Turn
Solve each compound inequality and graph the solutions
6 x - 5 ge -2 OR x -5 le -6
7 4x -1 lt 15 OR 8x ge 48
Explain 3 Creating Compound Inequalities From GraphsGiven a number line graph with a solution set graphed you can create a compound inequality to fit the graph
Example 3 Write the compound inequality shown by each graph
A
The shaded portion of the graph is not between two values so the compound inequality involves OR
On the left the graph shows an arrow pointing left from -1 and a solid circle so use le
The inequality is x le -1
On the right the graph shows an arrow pointing right from 7 and a solid circle so use ge
The inequality is x ge 7
The compound inequality is x le -1 OR x ge 7
B
The graph is shaded between the values and so the compound inequality involves AND
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The compound inequality is
-1 0 1 2 3 4 5-5-4 -3 -2
4 5 6 7 8 9 100 1 2 3
2 3 4 5 6 7 8-2 -1 0 1
10 2 3 4 5 6 7 8 9-1
Module 2 85 Lesson 5
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Reflect
8 What is a short method to write the compound inequality x ge 0 AND x lt 6
Your Turn
Write the compound inequality shown by each graph
9
10
Explain 4 Expressing Acceptable Levels with Compound Inequalities
You can express quality-controls levels in real-world problems using compound inequalities
Example 4 Write a compound inequality to represent the indicated quality-control level and graph the solutions
A The recommended pH level for swimming pool water is between 72 and 76 inclusive
Let p be the pH level of swimming pool water
72 is less than or equal to pH level is less than or equal to 76
72 le p le 76
The compound inequality is 72 le p le 76
Graph the solutions
0-10 -8-9 -7-6 -5-4 -3 -2 -1
71 72 73 74 75 76 77 78 79 8070
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 86 Lesson 5
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B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
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bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
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Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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bik
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onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
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cean
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orb
is
Solve for the indicated variable in each literal equation
11 2p + 5r = q for p 12 -10 = xy + z for x 13 a __ b = c for b
14 h - 4 _ j = k for j 15 x __ 5 - g = a for x 16 5p + 9c = p for c
17 2 __ 5 (z + 1) = y for z 18 g (h + 2 __ 3 ) = 1 for h 19 a(n - 3) + 8 = bn for n
20 Which is a possible way to rewrite the equation y = 3x + 3b to solve for b
A b = y - 3x
_ 3 C b = y - 3
_____ 3x
B b = 3(y - 3x) D b = x(y - 3)
21 Sports To find a baseball pitcherrsquos earned run average (ERA) you can use the formula Ei = 9r in which E represents ERA i represents the number of innings pitched and r represents the number of earned runs allowed Solve the equation for E What is a pitcherrsquos ERA if he allows 5 earned runs in 18 innings pitched
22 Meteorology For altitudes up to 36000 feet the relationship between ground temperature and atmospheric temperature can be described by the formula t = -00035a + g in which t is the atmospheric temperature in degrees Fahrenheit a is the altitude in feet at which the atmospheric temperature is measured and g is the ground temperature in degrees Fahrenheit Solve the equation for a If the atmospheric temperature is -655 ∘F and the ground temperature is 57 ∘F what is the altitude
Module 2 71 Lesson 3
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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Rand
y D
uch
aineA
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HOT Focus on Higher Order Thinking
23 Explain the Error A student was asked to use the formula for the perimeter of a rectangle P = 2ℓ + 2w to solve for ℓ The student came up with an answer P - 2w = 2ℓ What error did the student make Explain Then solve for ℓ
24 Multi-Step The formula c = 5p + 215 relates c the total cost in dollars of hosting a birthday party at a skating rink to p the number of people attending If Alliersquos parents are willing to spend $300 for a party how many people can attend
25 Multi-Step The formula for the area of a triangle is A = 1 __ 2 bh in which b represents the length of thebase and h represents the height If a triangle has an area of 192 mm2 and the height is 12 mm what is the measure of the base
Lesson Performance TaskThe following table shows the average low temperatures in Fahrenheit for the city of Boston for several months during the year The formula F = 9 __ 5 C + 32 allows you to determine the temperature in Fahrenheit when given the temperature in Celsius
MonthTemperature in
FahrenheitTemperature in
Celsius
January 22deg
April 41deg
July 65deg
October 47deg
December 28deg
a Use the information given to determine the average low temperatures in Celsius
b Would it ever be possible for the temperature in Celsius to have a greater value than the temperature in Fahrenheit Explain why or why not
Module 2 72 Lesson 3
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
Name Class Date
Resource Locker
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Patr
ick
Lan
eSo
mos
Imag
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orb
is
Explore Creating Inequalities from Verbal DescriptionsAn inequality is a statement that compares two expressions that are not strictly equal by using one of the following inequality signs
Symbol Meaning
lt is less than
le is less than or equal to
gt is greater than
ge is greater than or equal to
ne is not equal to
You have probably seen a sign at an amusement park saying something like ldquoYou must be at least 48 inches tall to ride this riderdquo This statement could be written as h ge 48 in where h represents the height of a person allowed to ride
Nora is planning a birthday party for her little sister Colleen Norarsquos budget will allow her to spend no more than $50 for party supplies Eight children including Colleen will attend the party and Nora wants to determine how much she could spend on party favors for each child She will also purchase a cake for $10 Write an inequality that represents the situation and find possible solutions
A First let c represent the cost of a party favor for each child Write an expression for the total cost of the party as a function of c
c +
B Which inequality symbol should be used to represent the phrase ldquono more thanrdquo
C Write the inequality that represents Norarsquos budget goal
8c + 10 le
D Suppose Nora finds party favors that cost $4 each Use a value of 4 for c and check to see if this inequality is true
8 middot 4 + 10 le 50
le 50
Module 2 73 Lesson 4
24 Creating and Solving Inequalities
Essential Question How do you write and solve an inequality that represents a real-world situation
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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pany
Is the inequality true
Could Nora buy $6 party favors for all of her guests without going over budget
Reflect
1 Why does an inequality represent Norarsquos budget calculation better than an equation
2 The solution set of an inequality consists of all values that make the statement true Describe the whole dollar amounts that are in the solution set for this situation
Explain 1 Creating and Solving Inequalities Involving the Distributive Property
You may need to use the Distributive Property before you can solve an inequality
Distributive Property If a b and c are real numbers then a(b + c) = ab + ac
The inequality sign must be reversed when multiplying or dividing both sides of an inequality by a negative number
Example 1
A Trina is buying 12 shirts for the drama club She will choose a style for the blank shirts and then pay an additional charge of $275 for each shirt to have the club logo If Trina cannot spend more than $99 how much can she spend on each blank shirt Write and solve an inequality to find the possible cost of each blank shirt
Let s represent the cost of each blank shirt
Write an inequality to represent the situation 12(s + 275) le 99
Use the Distributive Property 12s + 33 le 99
Subtraction Property of Inequality 12s + 33 - 33 le 99 - 33
Simplify 12s le 66
Division Property of Inequality 12s ___ 12 le 66 __ 12
Simplify s le 55
Module 2 74 Lesson 4
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Check your answer
Since s le 55 check a smaller number 12(5 + 275) le 99
Trina can order blank shirts that cost $550 or less 93 le 99 true
B Sergio needs to buy gifts for 8 friends He wants to give the same gift to all his friends and he plans to have the gifts wrapped for an additional charge of $150 each If Sergio spends at least $70 he will receive free shipping on his order Write and solve an inequality to determine how much Sergio needs to spend on each gift in order to receive free shipping
Let g be the cost of one gift
Write an inequality to represent the situation ( g + ) ge 70
Use the Distributive Property g + ge 70
Subtraction Property of Inequality g + 12 - ge 70 -
Simplify 8g ge
Division Property of Inequality 8g _
ge 58 _
Simplify g ge
Check your answer
Since g ge 725 check a larger number 8(8 + 150) ge 70
Sergio must spend at least on each gift ge 70
Reflect
3 Discussion Why is the first step in solving the inequality to use the Distributive Property instead of working inside the parentheses
Your Turn
4 Zachary is planning to send a video game to each of his two brothers If he buys the same game for both brothers and pays $475 to ship each game how much can he spend on each game without spending more than $100 Write and solve an inequality for this situation
Solve each inequality
5 4 _ 3 (6x + 9) lt 4 6 -2 ( 1 _ 4 x + 2 ) ge 5
Module 2 75 Lesson 4
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Explain 2 Creating and Solving Inequalities with Variables on Both Sides
Some inequalities have variable terms on both sides of the inequality symbol You can solve these inequalities the same way you solved equations with variables on both sides Use the properties of inequality to collect all the variable terms on one side and all the constant terms on the other side
Example 2
A The Daily Info charges a fee of $650 plus $80 per week to run an ad The Peoplersquos Paper charges $145 per week For how many weeks must an ad run for the total cost at the Daily Info to be less expensive than the cost at the Peoplersquos Paper Let w be the number of weeks the ad runs in the paper
Write an inequality to represent the situation 650 + 80w lt 145w
Subtraction Property of Inequality 650 + 80w - 80w lt 145w - 80w
Simplify 650 lt 65w
Division Property of Inequality 650 _ 65 lt 65w _ 65
Simplify 10 lt w
The total cost at the Daily Info is less than the cost at the Peoplersquos Paper if the ad runs for more than 10 weeks
B The Home Cleaning Company charges $312 to power-wash the siding of a house plus $12 for each window Power Clean charges $36 per window and the price includes power-washing the siding How many windows must a house have to make the total cost from The Home Cleaning Company less expensive than Power Clean Let w be the number of windows
Write an inequality to represent the situation +12w lt 36w
Subtraction Property of Inequality 312 + 12w - lt 36w -
Simplify 312 lt
Division Property of Inequality 312 _ lt 24w _
Simplify lt w
A house must have more than 13 windows for The Home Cleaning Company to be less expensive than Power Clean
Reflect
7 How would the final inequality change if you divided by ndash24 in the next to last step
Your Turn
8 The school band will sell pizzas to raise money for new uniforms The supplier charges $100 plus $4 per pizza The band members sell the pizzas for $7 each Write and solve an inequality to find how many pizzas the band members will have to sell to make a profit
Module 2 76 Lesson 4
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Elaborate
9 Which inequality symbol would you use to represent the following words or phrases Can you come up with more examples
a at most b farther than c younger than d up to
10 Discussion How are the steps to solving an inequality similar to those for solving an equation How are they different
11 Essential Question Check-In How can you write an inequality that represents a real-world situation
Write an inequality that represents the description and then solve
1 Max has more than 5 carrots (number of carrots Max has = c)
2 Brigitte is shorter than 5 feet (Brigittersquos height = h)
3 Twice a number (x) is less than 10 4 Six more than five times a number (x) is at least twenty-one
5 Dave has $15 to spend on an $8 book and two birthday cards (c) for his friends How much can he spend on each card if he buys the same card for each friend
6 Toni can carry up to 18 lb in her backpack Her lunch weighs 1 lb her gym clothes weigh 2 lb and her books (b) weigh 3 lb each How many books can she carry in her backpack
Evaluate Homework and Practice
bull Online Homeworkbull Hints and Helpbull Extra Practice
Module 2 77 Lesson 4
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pany
Solve each inequality
7 3 (x - 2) gt -3 8 5 + 5 (x + 4) le 20 9 3 + 1 _ 2 (3 - x) lt -7
10 3 (x + 6) - 2 (x + 2) ge 10 11 5 (3 - x) -4 (2 - 3x) gt 2 12 1 _ 2 (4x - 2) - 2 _ 3 (6x + 9) le 4
13 x + 1 gt -5 (7 - 2x) 14 5 _ 3 (6x + 3) le 2x - 7
15 2x le - 2 __ 3 (4x + 4) 16 1 __ 2 (-2x - 10) gt 3 (4 - 6x)
17 -5 - 3x ge 2 (10 + 2x) + 3 18 -3 (9x + 20) ge 15x - 20
19 8 ( 1 _ 4 x - 3) + 24 lt 4 ( x + 5 ) 20 6x - 2 (x + 2) gt 2 - 3 (x + 3)
Module 2 78 Lesson 4
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21 Physics A crane cable can support a maximum load of 15000 kg If a bucket has a mass of 2000 kg and gravel has a mass of 1500 kg for every cubic meter how many cubic meters of gravel (g) can be safely lifted by the crane
22 Find the solution set of each inequality below and then determine which inequalities have the same solution set as 1 _ 3 ( -5x - 3 ) lt 14
a 1 _ 3 (5x + 3) gt -14 b 2 _ 5 (10x + 20) gt 44
c - 2 _ 5 (10x + 20) lt -44 d - 1 _ 3 (5x + 3) lt 14
e 2 _ 5 (10x - 20) gt -44 f 1 _ 3 (5x + 3) lt -14
HOT Focus on Higher Order Thinking
23 Explain the Error Sven is trying to find the maximum amount of time he can spend practicing the five scales of piano music he is supposed to be working on He has 60 minutes to practice piano and would like to spend at least 35 minutes playing songs instead of practicing scales So Sven sets up the following inequality where t is the number of minutes he spends on each scale and solves it
60 - 5t le 35-5t le -25
t ge 5
Sven has concluded that he should spend 5 minutes or more on each scale Is this correct If not what mistake did he make Then solve for the correct answer
Module 2 79 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
24 Critical Thinking Anika wants to determine the maximum number of tulip bulbs (t) she can purchase if each bulb costs $150 She will also need to purchase separate pots for each bulb at $125 each and a bag of potting soil for $1000 Set up an inequality to determine how many tulip bulbs Anika can purchase without spending more than $2000 and solve it Can Anika buy exactly enough bulbs and pots to spend the full $2000 Explain Can you think of a better inequality to describe the answer
25 Geometry The area of the triangle shown is no more than 10 square inches
a Write an inequality that can be used to find x
b Solve the inequality from part a c What is the maximum height of the triangle
Lesson Performance TaskWhen planning an airplane route the trip planner must be careful to consider the range the aircraft can travel and the availability of airports to stop and refuel
A large commercial jet airplane burns approximately 5 gallons of fuel per mile flown plus about 8500 gallons of fuel per trip to reach cruising altitude With a useable fuel capacity of 50000 gallons (there is additional fuel reserved for emergencies) describe the acceptable distance for which an airline could establish a non-stop flight
For flights originating from Chicago determine which cities could be safely reached by a non-stop flight
City Distance from Chicago (miles)
Bangalore India 8530
Jakarta Indonesia 9810
Johannesburg South Africa 8680
Moscow Russia 4970
Paris France 4130
Perth Australia 10970
Tokyo Japan 6300
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oug
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its copySarych
eva O
lesiaShutterstock
(2x - 3) in
4 in
Module 2 80 Lesson 4
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Name Class Date
Resource Locker
Explore Truth Tables and Compound StatementsA compound statement is formed by combining two or more simple statements A compound statement can be true or false A compound statement involving AND is true when both simple statements are true A compound statement involving OR is true when either one simple statement or both are true
A Complete the truth table
P QP
True or FalseQ
True or FalseP AND Q
True or False
A dog is a mammal Red is a color
A dog is a mammal Red is not a color
A dog is a fish Red is a color
A dog is a fish Red is not a color
B P AND Q is true when
C Complete the truth table
P QP
True or FalseQ
True or FalseP OR Q
True or False
1 is an odd number 2 is an even number
1 is an odd number 2 is an odd number
1 is an even number 2 is an even number
1 is an even number 2 is an odd number
D P OR Q is true when
Reflect
1 Give two simple statements P and Q for which P AND Q is false and P OR Q is true
Module 2 81 Lesson 5
25 Creating and Solving Compound Inequalities
Essential Question How can you solve a compound inequality and graph the solution set
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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Explain 1 Solving Compound Inequalities Involving ANDCombining two or more simple inequalities forms a compound inequality The graph of a compound inequality involving AND is the intersection or the overlapping region of the simple inequality graphs
Compound Inequalities AND
Words Algebra Graph
All real numbers greater than 2AND less than 6
x gt 2 AND x lt 62 lt x lt 6
All real numbers greater than or equal to 2 AND less than or equal to 6
x ge 2 AND x le 62 le x le 6
Example 1 Solve each compound inequality and graph the solutions
A 4 le x + 2 le 8
4 le x + 2 AND x + 2 le 8 Write the compound inequality using AND
4 - 2 le x + 2 - 2 x + 2 - 2 le 8 - 2 Subtract 2 from both sides of each simple inequality
2 le x x le 6 Simplify
Graph 2 le x
Graph x le 6
Graph the intersection by finding where the two graphs overlap
B -5 le 2x + 3 lt 9
-5 - le 2x + 3 - lt 9 - Subtract from each part of the inequality
le 2x lt Simplify
-8 _ le 2x _ lt 6 _ Divide each part of the inequality by
le x lt Simplify
Graph -4 le x
Graph x lt 3
Graph the intersection by finding where the two graphs overlap -1 0 1 2 3 4 5-5-4 -3 -2
0 2 4 6 8 10 12-8-6-4 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 82 Lesson 5
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Reflect
2 Discussion Explain why 2 le x le 6 can be considered the short method for writing the AND compound inequality x ge 2 AND x le 6
YourTurn
Solve each compound inequality and graph the solutions
3 -2 lt x - 3 lt 5
4 -10 lt 3x + 2 le 8
Explain 2 Solving Compound Inequalities Involving ORThe graph of a compound inequality involving OR is the union or the combined region of the simple inequality graphs
Compound Inequalities OR
Words Algebra Graph
All real numbers less than 2OR greater than 6
x lt 2 OR x gt 6
All real numbers less than or equal to 2OR greater than or equal to 6
x le 2 OR x ge 6
-1 0 1 2 3 4 5-5-4 -3 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 83 Lesson 5
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Example 2 Solve each compound inequality and graph the solutions
A -4 + x gt 1 OR -4 + x lt -3
-4 + x gt 1 OR -4 + x lt -3 Write the compound inequality using OR
-4 + 4 + x gt 1 + 4 -4 + 4 + x lt -3 + 4 Add 4 to both sides of each simple inequality
x gt 5 x lt 1 Simplify
Graph x gt 5
Graph x lt 1
Graph the union by combining the graphs
B 2x le 6 OR 3x gt 12
2x le 6 OR 3x gt 12 Write the compound inequality using OR
2x _ le 6 _ OR 3x _ gt 12 _ Divide the first simple inequality by
x le OR x gt
Graph x le 3
Graph x gt 4
Graph the union by combining the graphs
Reflect
5 Critical Thinking What kind of compound inequality has no solution
Divide the second simple inequality by
Simplify
0 1 2 3 4 5 6-4 -3 -2 -1
-0 1 2 3 4 5 6-4 -3 -2 -1
Module 2 84 Lesson 5
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Your Turn
Solve each compound inequality and graph the solutions
6 x - 5 ge -2 OR x -5 le -6
7 4x -1 lt 15 OR 8x ge 48
Explain 3 Creating Compound Inequalities From GraphsGiven a number line graph with a solution set graphed you can create a compound inequality to fit the graph
Example 3 Write the compound inequality shown by each graph
A
The shaded portion of the graph is not between two values so the compound inequality involves OR
On the left the graph shows an arrow pointing left from -1 and a solid circle so use le
The inequality is x le -1
On the right the graph shows an arrow pointing right from 7 and a solid circle so use ge
The inequality is x ge 7
The compound inequality is x le -1 OR x ge 7
B
The graph is shaded between the values and so the compound inequality involves AND
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The compound inequality is
-1 0 1 2 3 4 5-5-4 -3 -2
4 5 6 7 8 9 100 1 2 3
2 3 4 5 6 7 8-2 -1 0 1
10 2 3 4 5 6 7 8 9-1
Module 2 85 Lesson 5
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Reflect
8 What is a short method to write the compound inequality x ge 0 AND x lt 6
Your Turn
Write the compound inequality shown by each graph
9
10
Explain 4 Expressing Acceptable Levels with Compound Inequalities
You can express quality-controls levels in real-world problems using compound inequalities
Example 4 Write a compound inequality to represent the indicated quality-control level and graph the solutions
A The recommended pH level for swimming pool water is between 72 and 76 inclusive
Let p be the pH level of swimming pool water
72 is less than or equal to pH level is less than or equal to 76
72 le p le 76
The compound inequality is 72 le p le 76
Graph the solutions
0-10 -8-9 -7-6 -5-4 -3 -2 -1
71 72 73 74 75 76 77 78 79 8070
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 86 Lesson 5
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B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
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bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
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Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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age C
redits copy
Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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Com
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mag
e C
red
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copy
bik
erid
erlo
nd
onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
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The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
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Rand
y D
uch
aineA
lamy
HOT Focus on Higher Order Thinking
23 Explain the Error A student was asked to use the formula for the perimeter of a rectangle P = 2ℓ + 2w to solve for ℓ The student came up with an answer P - 2w = 2ℓ What error did the student make Explain Then solve for ℓ
24 Multi-Step The formula c = 5p + 215 relates c the total cost in dollars of hosting a birthday party at a skating rink to p the number of people attending If Alliersquos parents are willing to spend $300 for a party how many people can attend
25 Multi-Step The formula for the area of a triangle is A = 1 __ 2 bh in which b represents the length of thebase and h represents the height If a triangle has an area of 192 mm2 and the height is 12 mm what is the measure of the base
Lesson Performance TaskThe following table shows the average low temperatures in Fahrenheit for the city of Boston for several months during the year The formula F = 9 __ 5 C + 32 allows you to determine the temperature in Fahrenheit when given the temperature in Celsius
MonthTemperature in
FahrenheitTemperature in
Celsius
January 22deg
April 41deg
July 65deg
October 47deg
December 28deg
a Use the information given to determine the average low temperatures in Celsius
b Would it ever be possible for the temperature in Celsius to have a greater value than the temperature in Fahrenheit Explain why or why not
Module 2 72 Lesson 3
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
Name Class Date
Resource Locker
copy H
oug
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Mif
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Har
cour
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lishi
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Com
pan
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mag
e cr
edit
s copy
Patr
ick
Lan
eSo
mos
Imag
esC
orb
is
Explore Creating Inequalities from Verbal DescriptionsAn inequality is a statement that compares two expressions that are not strictly equal by using one of the following inequality signs
Symbol Meaning
lt is less than
le is less than or equal to
gt is greater than
ge is greater than or equal to
ne is not equal to
You have probably seen a sign at an amusement park saying something like ldquoYou must be at least 48 inches tall to ride this riderdquo This statement could be written as h ge 48 in where h represents the height of a person allowed to ride
Nora is planning a birthday party for her little sister Colleen Norarsquos budget will allow her to spend no more than $50 for party supplies Eight children including Colleen will attend the party and Nora wants to determine how much she could spend on party favors for each child She will also purchase a cake for $10 Write an inequality that represents the situation and find possible solutions
A First let c represent the cost of a party favor for each child Write an expression for the total cost of the party as a function of c
c +
B Which inequality symbol should be used to represent the phrase ldquono more thanrdquo
C Write the inequality that represents Norarsquos budget goal
8c + 10 le
D Suppose Nora finds party favors that cost $4 each Use a value of 4 for c and check to see if this inequality is true
8 middot 4 + 10 le 50
le 50
Module 2 73 Lesson 4
24 Creating and Solving Inequalities
Essential Question How do you write and solve an inequality that represents a real-world situation
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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pany
Is the inequality true
Could Nora buy $6 party favors for all of her guests without going over budget
Reflect
1 Why does an inequality represent Norarsquos budget calculation better than an equation
2 The solution set of an inequality consists of all values that make the statement true Describe the whole dollar amounts that are in the solution set for this situation
Explain 1 Creating and Solving Inequalities Involving the Distributive Property
You may need to use the Distributive Property before you can solve an inequality
Distributive Property If a b and c are real numbers then a(b + c) = ab + ac
The inequality sign must be reversed when multiplying or dividing both sides of an inequality by a negative number
Example 1
A Trina is buying 12 shirts for the drama club She will choose a style for the blank shirts and then pay an additional charge of $275 for each shirt to have the club logo If Trina cannot spend more than $99 how much can she spend on each blank shirt Write and solve an inequality to find the possible cost of each blank shirt
Let s represent the cost of each blank shirt
Write an inequality to represent the situation 12(s + 275) le 99
Use the Distributive Property 12s + 33 le 99
Subtraction Property of Inequality 12s + 33 - 33 le 99 - 33
Simplify 12s le 66
Division Property of Inequality 12s ___ 12 le 66 __ 12
Simplify s le 55
Module 2 74 Lesson 4
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pan
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Check your answer
Since s le 55 check a smaller number 12(5 + 275) le 99
Trina can order blank shirts that cost $550 or less 93 le 99 true
B Sergio needs to buy gifts for 8 friends He wants to give the same gift to all his friends and he plans to have the gifts wrapped for an additional charge of $150 each If Sergio spends at least $70 he will receive free shipping on his order Write and solve an inequality to determine how much Sergio needs to spend on each gift in order to receive free shipping
Let g be the cost of one gift
Write an inequality to represent the situation ( g + ) ge 70
Use the Distributive Property g + ge 70
Subtraction Property of Inequality g + 12 - ge 70 -
Simplify 8g ge
Division Property of Inequality 8g _
ge 58 _
Simplify g ge
Check your answer
Since g ge 725 check a larger number 8(8 + 150) ge 70
Sergio must spend at least on each gift ge 70
Reflect
3 Discussion Why is the first step in solving the inequality to use the Distributive Property instead of working inside the parentheses
Your Turn
4 Zachary is planning to send a video game to each of his two brothers If he buys the same game for both brothers and pays $475 to ship each game how much can he spend on each game without spending more than $100 Write and solve an inequality for this situation
Solve each inequality
5 4 _ 3 (6x + 9) lt 4 6 -2 ( 1 _ 4 x + 2 ) ge 5
Module 2 75 Lesson 4
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oug
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Explain 2 Creating and Solving Inequalities with Variables on Both Sides
Some inequalities have variable terms on both sides of the inequality symbol You can solve these inequalities the same way you solved equations with variables on both sides Use the properties of inequality to collect all the variable terms on one side and all the constant terms on the other side
Example 2
A The Daily Info charges a fee of $650 plus $80 per week to run an ad The Peoplersquos Paper charges $145 per week For how many weeks must an ad run for the total cost at the Daily Info to be less expensive than the cost at the Peoplersquos Paper Let w be the number of weeks the ad runs in the paper
Write an inequality to represent the situation 650 + 80w lt 145w
Subtraction Property of Inequality 650 + 80w - 80w lt 145w - 80w
Simplify 650 lt 65w
Division Property of Inequality 650 _ 65 lt 65w _ 65
Simplify 10 lt w
The total cost at the Daily Info is less than the cost at the Peoplersquos Paper if the ad runs for more than 10 weeks
B The Home Cleaning Company charges $312 to power-wash the siding of a house plus $12 for each window Power Clean charges $36 per window and the price includes power-washing the siding How many windows must a house have to make the total cost from The Home Cleaning Company less expensive than Power Clean Let w be the number of windows
Write an inequality to represent the situation +12w lt 36w
Subtraction Property of Inequality 312 + 12w - lt 36w -
Simplify 312 lt
Division Property of Inequality 312 _ lt 24w _
Simplify lt w
A house must have more than 13 windows for The Home Cleaning Company to be less expensive than Power Clean
Reflect
7 How would the final inequality change if you divided by ndash24 in the next to last step
Your Turn
8 The school band will sell pizzas to raise money for new uniforms The supplier charges $100 plus $4 per pizza The band members sell the pizzas for $7 each Write and solve an inequality to find how many pizzas the band members will have to sell to make a profit
Module 2 76 Lesson 4
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Elaborate
9 Which inequality symbol would you use to represent the following words or phrases Can you come up with more examples
a at most b farther than c younger than d up to
10 Discussion How are the steps to solving an inequality similar to those for solving an equation How are they different
11 Essential Question Check-In How can you write an inequality that represents a real-world situation
Write an inequality that represents the description and then solve
1 Max has more than 5 carrots (number of carrots Max has = c)
2 Brigitte is shorter than 5 feet (Brigittersquos height = h)
3 Twice a number (x) is less than 10 4 Six more than five times a number (x) is at least twenty-one
5 Dave has $15 to spend on an $8 book and two birthday cards (c) for his friends How much can he spend on each card if he buys the same card for each friend
6 Toni can carry up to 18 lb in her backpack Her lunch weighs 1 lb her gym clothes weigh 2 lb and her books (b) weigh 3 lb each How many books can she carry in her backpack
Evaluate Homework and Practice
bull Online Homeworkbull Hints and Helpbull Extra Practice
Module 2 77 Lesson 4
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pany
Solve each inequality
7 3 (x - 2) gt -3 8 5 + 5 (x + 4) le 20 9 3 + 1 _ 2 (3 - x) lt -7
10 3 (x + 6) - 2 (x + 2) ge 10 11 5 (3 - x) -4 (2 - 3x) gt 2 12 1 _ 2 (4x - 2) - 2 _ 3 (6x + 9) le 4
13 x + 1 gt -5 (7 - 2x) 14 5 _ 3 (6x + 3) le 2x - 7
15 2x le - 2 __ 3 (4x + 4) 16 1 __ 2 (-2x - 10) gt 3 (4 - 6x)
17 -5 - 3x ge 2 (10 + 2x) + 3 18 -3 (9x + 20) ge 15x - 20
19 8 ( 1 _ 4 x - 3) + 24 lt 4 ( x + 5 ) 20 6x - 2 (x + 2) gt 2 - 3 (x + 3)
Module 2 78 Lesson 4
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oug
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21 Physics A crane cable can support a maximum load of 15000 kg If a bucket has a mass of 2000 kg and gravel has a mass of 1500 kg for every cubic meter how many cubic meters of gravel (g) can be safely lifted by the crane
22 Find the solution set of each inequality below and then determine which inequalities have the same solution set as 1 _ 3 ( -5x - 3 ) lt 14
a 1 _ 3 (5x + 3) gt -14 b 2 _ 5 (10x + 20) gt 44
c - 2 _ 5 (10x + 20) lt -44 d - 1 _ 3 (5x + 3) lt 14
e 2 _ 5 (10x - 20) gt -44 f 1 _ 3 (5x + 3) lt -14
HOT Focus on Higher Order Thinking
23 Explain the Error Sven is trying to find the maximum amount of time he can spend practicing the five scales of piano music he is supposed to be working on He has 60 minutes to practice piano and would like to spend at least 35 minutes playing songs instead of practicing scales So Sven sets up the following inequality where t is the number of minutes he spends on each scale and solves it
60 - 5t le 35-5t le -25
t ge 5
Sven has concluded that he should spend 5 minutes or more on each scale Is this correct If not what mistake did he make Then solve for the correct answer
Module 2 79 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
24 Critical Thinking Anika wants to determine the maximum number of tulip bulbs (t) she can purchase if each bulb costs $150 She will also need to purchase separate pots for each bulb at $125 each and a bag of potting soil for $1000 Set up an inequality to determine how many tulip bulbs Anika can purchase without spending more than $2000 and solve it Can Anika buy exactly enough bulbs and pots to spend the full $2000 Explain Can you think of a better inequality to describe the answer
25 Geometry The area of the triangle shown is no more than 10 square inches
a Write an inequality that can be used to find x
b Solve the inequality from part a c What is the maximum height of the triangle
Lesson Performance TaskWhen planning an airplane route the trip planner must be careful to consider the range the aircraft can travel and the availability of airports to stop and refuel
A large commercial jet airplane burns approximately 5 gallons of fuel per mile flown plus about 8500 gallons of fuel per trip to reach cruising altitude With a useable fuel capacity of 50000 gallons (there is additional fuel reserved for emergencies) describe the acceptable distance for which an airline could establish a non-stop flight
For flights originating from Chicago determine which cities could be safely reached by a non-stop flight
City Distance from Chicago (miles)
Bangalore India 8530
Jakarta Indonesia 9810
Johannesburg South Africa 8680
Moscow Russia 4970
Paris France 4130
Perth Australia 10970
Tokyo Japan 6300
copy H
oug
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age cred
its copySarych
eva O
lesiaShutterstock
(2x - 3) in
4 in
Module 2 80 Lesson 4
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oug
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Name Class Date
Resource Locker
Explore Truth Tables and Compound StatementsA compound statement is formed by combining two or more simple statements A compound statement can be true or false A compound statement involving AND is true when both simple statements are true A compound statement involving OR is true when either one simple statement or both are true
A Complete the truth table
P QP
True or FalseQ
True or FalseP AND Q
True or False
A dog is a mammal Red is a color
A dog is a mammal Red is not a color
A dog is a fish Red is a color
A dog is a fish Red is not a color
B P AND Q is true when
C Complete the truth table
P QP
True or FalseQ
True or FalseP OR Q
True or False
1 is an odd number 2 is an even number
1 is an odd number 2 is an odd number
1 is an even number 2 is an even number
1 is an even number 2 is an odd number
D P OR Q is true when
Reflect
1 Give two simple statements P and Q for which P AND Q is false and P OR Q is true
Module 2 81 Lesson 5
25 Creating and Solving Compound Inequalities
Essential Question How can you solve a compound inequality and graph the solution set
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
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pany
Explain 1 Solving Compound Inequalities Involving ANDCombining two or more simple inequalities forms a compound inequality The graph of a compound inequality involving AND is the intersection or the overlapping region of the simple inequality graphs
Compound Inequalities AND
Words Algebra Graph
All real numbers greater than 2AND less than 6
x gt 2 AND x lt 62 lt x lt 6
All real numbers greater than or equal to 2 AND less than or equal to 6
x ge 2 AND x le 62 le x le 6
Example 1 Solve each compound inequality and graph the solutions
A 4 le x + 2 le 8
4 le x + 2 AND x + 2 le 8 Write the compound inequality using AND
4 - 2 le x + 2 - 2 x + 2 - 2 le 8 - 2 Subtract 2 from both sides of each simple inequality
2 le x x le 6 Simplify
Graph 2 le x
Graph x le 6
Graph the intersection by finding where the two graphs overlap
B -5 le 2x + 3 lt 9
-5 - le 2x + 3 - lt 9 - Subtract from each part of the inequality
le 2x lt Simplify
-8 _ le 2x _ lt 6 _ Divide each part of the inequality by
le x lt Simplify
Graph -4 le x
Graph x lt 3
Graph the intersection by finding where the two graphs overlap -1 0 1 2 3 4 5-5-4 -3 -2
0 2 4 6 8 10 12-8-6-4 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 82 Lesson 5
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oug
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Reflect
2 Discussion Explain why 2 le x le 6 can be considered the short method for writing the AND compound inequality x ge 2 AND x le 6
YourTurn
Solve each compound inequality and graph the solutions
3 -2 lt x - 3 lt 5
4 -10 lt 3x + 2 le 8
Explain 2 Solving Compound Inequalities Involving ORThe graph of a compound inequality involving OR is the union or the combined region of the simple inequality graphs
Compound Inequalities OR
Words Algebra Graph
All real numbers less than 2OR greater than 6
x lt 2 OR x gt 6
All real numbers less than or equal to 2OR greater than or equal to 6
x le 2 OR x ge 6
-1 0 1 2 3 4 5-5-4 -3 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 83 Lesson 5
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oug
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pany
Example 2 Solve each compound inequality and graph the solutions
A -4 + x gt 1 OR -4 + x lt -3
-4 + x gt 1 OR -4 + x lt -3 Write the compound inequality using OR
-4 + 4 + x gt 1 + 4 -4 + 4 + x lt -3 + 4 Add 4 to both sides of each simple inequality
x gt 5 x lt 1 Simplify
Graph x gt 5
Graph x lt 1
Graph the union by combining the graphs
B 2x le 6 OR 3x gt 12
2x le 6 OR 3x gt 12 Write the compound inequality using OR
2x _ le 6 _ OR 3x _ gt 12 _ Divide the first simple inequality by
x le OR x gt
Graph x le 3
Graph x gt 4
Graph the union by combining the graphs
Reflect
5 Critical Thinking What kind of compound inequality has no solution
Divide the second simple inequality by
Simplify
0 1 2 3 4 5 6-4 -3 -2 -1
-0 1 2 3 4 5 6-4 -3 -2 -1
Module 2 84 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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Your Turn
Solve each compound inequality and graph the solutions
6 x - 5 ge -2 OR x -5 le -6
7 4x -1 lt 15 OR 8x ge 48
Explain 3 Creating Compound Inequalities From GraphsGiven a number line graph with a solution set graphed you can create a compound inequality to fit the graph
Example 3 Write the compound inequality shown by each graph
A
The shaded portion of the graph is not between two values so the compound inequality involves OR
On the left the graph shows an arrow pointing left from -1 and a solid circle so use le
The inequality is x le -1
On the right the graph shows an arrow pointing right from 7 and a solid circle so use ge
The inequality is x ge 7
The compound inequality is x le -1 OR x ge 7
B
The graph is shaded between the values and so the compound inequality involves AND
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The compound inequality is
-1 0 1 2 3 4 5-5-4 -3 -2
4 5 6 7 8 9 100 1 2 3
2 3 4 5 6 7 8-2 -1 0 1
10 2 3 4 5 6 7 8 9-1
Module 2 85 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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oug
hton Mifflin H
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pany
Reflect
8 What is a short method to write the compound inequality x ge 0 AND x lt 6
Your Turn
Write the compound inequality shown by each graph
9
10
Explain 4 Expressing Acceptable Levels with Compound Inequalities
You can express quality-controls levels in real-world problems using compound inequalities
Example 4 Write a compound inequality to represent the indicated quality-control level and graph the solutions
A The recommended pH level for swimming pool water is between 72 and 76 inclusive
Let p be the pH level of swimming pool water
72 is less than or equal to pH level is less than or equal to 76
72 le p le 76
The compound inequality is 72 le p le 76
Graph the solutions
0-10 -8-9 -7-6 -5-4 -3 -2 -1
71 72 73 74 75 76 77 78 79 8070
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 86 Lesson 5
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B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
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oug
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pany
bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
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Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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arcourt Publishin
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pany bull Im
age C
redits copy
Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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Mif
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cour
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Com
pan
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mag
e C
red
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copy
bik
erid
erlo
nd
onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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pany
The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
Name Class Date
Resource Locker
copy H
oug
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Mif
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Har
cour
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Com
pan
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mag
e cr
edit
s copy
Patr
ick
Lan
eSo
mos
Imag
esC
orb
is
Explore Creating Inequalities from Verbal DescriptionsAn inequality is a statement that compares two expressions that are not strictly equal by using one of the following inequality signs
Symbol Meaning
lt is less than
le is less than or equal to
gt is greater than
ge is greater than or equal to
ne is not equal to
You have probably seen a sign at an amusement park saying something like ldquoYou must be at least 48 inches tall to ride this riderdquo This statement could be written as h ge 48 in where h represents the height of a person allowed to ride
Nora is planning a birthday party for her little sister Colleen Norarsquos budget will allow her to spend no more than $50 for party supplies Eight children including Colleen will attend the party and Nora wants to determine how much she could spend on party favors for each child She will also purchase a cake for $10 Write an inequality that represents the situation and find possible solutions
A First let c represent the cost of a party favor for each child Write an expression for the total cost of the party as a function of c
c +
B Which inequality symbol should be used to represent the phrase ldquono more thanrdquo
C Write the inequality that represents Norarsquos budget goal
8c + 10 le
D Suppose Nora finds party favors that cost $4 each Use a value of 4 for c and check to see if this inequality is true
8 middot 4 + 10 le 50
le 50
Module 2 73 Lesson 4
24 Creating and Solving Inequalities
Essential Question How do you write and solve an inequality that represents a real-world situation
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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pany
Is the inequality true
Could Nora buy $6 party favors for all of her guests without going over budget
Reflect
1 Why does an inequality represent Norarsquos budget calculation better than an equation
2 The solution set of an inequality consists of all values that make the statement true Describe the whole dollar amounts that are in the solution set for this situation
Explain 1 Creating and Solving Inequalities Involving the Distributive Property
You may need to use the Distributive Property before you can solve an inequality
Distributive Property If a b and c are real numbers then a(b + c) = ab + ac
The inequality sign must be reversed when multiplying or dividing both sides of an inequality by a negative number
Example 1
A Trina is buying 12 shirts for the drama club She will choose a style for the blank shirts and then pay an additional charge of $275 for each shirt to have the club logo If Trina cannot spend more than $99 how much can she spend on each blank shirt Write and solve an inequality to find the possible cost of each blank shirt
Let s represent the cost of each blank shirt
Write an inequality to represent the situation 12(s + 275) le 99
Use the Distributive Property 12s + 33 le 99
Subtraction Property of Inequality 12s + 33 - 33 le 99 - 33
Simplify 12s le 66
Division Property of Inequality 12s ___ 12 le 66 __ 12
Simplify s le 55
Module 2 74 Lesson 4
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Check your answer
Since s le 55 check a smaller number 12(5 + 275) le 99
Trina can order blank shirts that cost $550 or less 93 le 99 true
B Sergio needs to buy gifts for 8 friends He wants to give the same gift to all his friends and he plans to have the gifts wrapped for an additional charge of $150 each If Sergio spends at least $70 he will receive free shipping on his order Write and solve an inequality to determine how much Sergio needs to spend on each gift in order to receive free shipping
Let g be the cost of one gift
Write an inequality to represent the situation ( g + ) ge 70
Use the Distributive Property g + ge 70
Subtraction Property of Inequality g + 12 - ge 70 -
Simplify 8g ge
Division Property of Inequality 8g _
ge 58 _
Simplify g ge
Check your answer
Since g ge 725 check a larger number 8(8 + 150) ge 70
Sergio must spend at least on each gift ge 70
Reflect
3 Discussion Why is the first step in solving the inequality to use the Distributive Property instead of working inside the parentheses
Your Turn
4 Zachary is planning to send a video game to each of his two brothers If he buys the same game for both brothers and pays $475 to ship each game how much can he spend on each game without spending more than $100 Write and solve an inequality for this situation
Solve each inequality
5 4 _ 3 (6x + 9) lt 4 6 -2 ( 1 _ 4 x + 2 ) ge 5
Module 2 75 Lesson 4
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Explain 2 Creating and Solving Inequalities with Variables on Both Sides
Some inequalities have variable terms on both sides of the inequality symbol You can solve these inequalities the same way you solved equations with variables on both sides Use the properties of inequality to collect all the variable terms on one side and all the constant terms on the other side
Example 2
A The Daily Info charges a fee of $650 plus $80 per week to run an ad The Peoplersquos Paper charges $145 per week For how many weeks must an ad run for the total cost at the Daily Info to be less expensive than the cost at the Peoplersquos Paper Let w be the number of weeks the ad runs in the paper
Write an inequality to represent the situation 650 + 80w lt 145w
Subtraction Property of Inequality 650 + 80w - 80w lt 145w - 80w
Simplify 650 lt 65w
Division Property of Inequality 650 _ 65 lt 65w _ 65
Simplify 10 lt w
The total cost at the Daily Info is less than the cost at the Peoplersquos Paper if the ad runs for more than 10 weeks
B The Home Cleaning Company charges $312 to power-wash the siding of a house plus $12 for each window Power Clean charges $36 per window and the price includes power-washing the siding How many windows must a house have to make the total cost from The Home Cleaning Company less expensive than Power Clean Let w be the number of windows
Write an inequality to represent the situation +12w lt 36w
Subtraction Property of Inequality 312 + 12w - lt 36w -
Simplify 312 lt
Division Property of Inequality 312 _ lt 24w _
Simplify lt w
A house must have more than 13 windows for The Home Cleaning Company to be less expensive than Power Clean
Reflect
7 How would the final inequality change if you divided by ndash24 in the next to last step
Your Turn
8 The school band will sell pizzas to raise money for new uniforms The supplier charges $100 plus $4 per pizza The band members sell the pizzas for $7 each Write and solve an inequality to find how many pizzas the band members will have to sell to make a profit
Module 2 76 Lesson 4
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Elaborate
9 Which inequality symbol would you use to represent the following words or phrases Can you come up with more examples
a at most b farther than c younger than d up to
10 Discussion How are the steps to solving an inequality similar to those for solving an equation How are they different
11 Essential Question Check-In How can you write an inequality that represents a real-world situation
Write an inequality that represents the description and then solve
1 Max has more than 5 carrots (number of carrots Max has = c)
2 Brigitte is shorter than 5 feet (Brigittersquos height = h)
3 Twice a number (x) is less than 10 4 Six more than five times a number (x) is at least twenty-one
5 Dave has $15 to spend on an $8 book and two birthday cards (c) for his friends How much can he spend on each card if he buys the same card for each friend
6 Toni can carry up to 18 lb in her backpack Her lunch weighs 1 lb her gym clothes weigh 2 lb and her books (b) weigh 3 lb each How many books can she carry in her backpack
Evaluate Homework and Practice
bull Online Homeworkbull Hints and Helpbull Extra Practice
Module 2 77 Lesson 4
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Solve each inequality
7 3 (x - 2) gt -3 8 5 + 5 (x + 4) le 20 9 3 + 1 _ 2 (3 - x) lt -7
10 3 (x + 6) - 2 (x + 2) ge 10 11 5 (3 - x) -4 (2 - 3x) gt 2 12 1 _ 2 (4x - 2) - 2 _ 3 (6x + 9) le 4
13 x + 1 gt -5 (7 - 2x) 14 5 _ 3 (6x + 3) le 2x - 7
15 2x le - 2 __ 3 (4x + 4) 16 1 __ 2 (-2x - 10) gt 3 (4 - 6x)
17 -5 - 3x ge 2 (10 + 2x) + 3 18 -3 (9x + 20) ge 15x - 20
19 8 ( 1 _ 4 x - 3) + 24 lt 4 ( x + 5 ) 20 6x - 2 (x + 2) gt 2 - 3 (x + 3)
Module 2 78 Lesson 4
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21 Physics A crane cable can support a maximum load of 15000 kg If a bucket has a mass of 2000 kg and gravel has a mass of 1500 kg for every cubic meter how many cubic meters of gravel (g) can be safely lifted by the crane
22 Find the solution set of each inequality below and then determine which inequalities have the same solution set as 1 _ 3 ( -5x - 3 ) lt 14
a 1 _ 3 (5x + 3) gt -14 b 2 _ 5 (10x + 20) gt 44
c - 2 _ 5 (10x + 20) lt -44 d - 1 _ 3 (5x + 3) lt 14
e 2 _ 5 (10x - 20) gt -44 f 1 _ 3 (5x + 3) lt -14
HOT Focus on Higher Order Thinking
23 Explain the Error Sven is trying to find the maximum amount of time he can spend practicing the five scales of piano music he is supposed to be working on He has 60 minutes to practice piano and would like to spend at least 35 minutes playing songs instead of practicing scales So Sven sets up the following inequality where t is the number of minutes he spends on each scale and solves it
60 - 5t le 35-5t le -25
t ge 5
Sven has concluded that he should spend 5 minutes or more on each scale Is this correct If not what mistake did he make Then solve for the correct answer
Module 2 79 Lesson 4
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24 Critical Thinking Anika wants to determine the maximum number of tulip bulbs (t) she can purchase if each bulb costs $150 She will also need to purchase separate pots for each bulb at $125 each and a bag of potting soil for $1000 Set up an inequality to determine how many tulip bulbs Anika can purchase without spending more than $2000 and solve it Can Anika buy exactly enough bulbs and pots to spend the full $2000 Explain Can you think of a better inequality to describe the answer
25 Geometry The area of the triangle shown is no more than 10 square inches
a Write an inequality that can be used to find x
b Solve the inequality from part a c What is the maximum height of the triangle
Lesson Performance TaskWhen planning an airplane route the trip planner must be careful to consider the range the aircraft can travel and the availability of airports to stop and refuel
A large commercial jet airplane burns approximately 5 gallons of fuel per mile flown plus about 8500 gallons of fuel per trip to reach cruising altitude With a useable fuel capacity of 50000 gallons (there is additional fuel reserved for emergencies) describe the acceptable distance for which an airline could establish a non-stop flight
For flights originating from Chicago determine which cities could be safely reached by a non-stop flight
City Distance from Chicago (miles)
Bangalore India 8530
Jakarta Indonesia 9810
Johannesburg South Africa 8680
Moscow Russia 4970
Paris France 4130
Perth Australia 10970
Tokyo Japan 6300
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oug
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age cred
its copySarych
eva O
lesiaShutterstock
(2x - 3) in
4 in
Module 2 80 Lesson 4
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oug
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Name Class Date
Resource Locker
Explore Truth Tables and Compound StatementsA compound statement is formed by combining two or more simple statements A compound statement can be true or false A compound statement involving AND is true when both simple statements are true A compound statement involving OR is true when either one simple statement or both are true
A Complete the truth table
P QP
True or FalseQ
True or FalseP AND Q
True or False
A dog is a mammal Red is a color
A dog is a mammal Red is not a color
A dog is a fish Red is a color
A dog is a fish Red is not a color
B P AND Q is true when
C Complete the truth table
P QP
True or FalseQ
True or FalseP OR Q
True or False
1 is an odd number 2 is an even number
1 is an odd number 2 is an odd number
1 is an even number 2 is an even number
1 is an even number 2 is an odd number
D P OR Q is true when
Reflect
1 Give two simple statements P and Q for which P AND Q is false and P OR Q is true
Module 2 81 Lesson 5
25 Creating and Solving Compound Inequalities
Essential Question How can you solve a compound inequality and graph the solution set
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Explain 1 Solving Compound Inequalities Involving ANDCombining two or more simple inequalities forms a compound inequality The graph of a compound inequality involving AND is the intersection or the overlapping region of the simple inequality graphs
Compound Inequalities AND
Words Algebra Graph
All real numbers greater than 2AND less than 6
x gt 2 AND x lt 62 lt x lt 6
All real numbers greater than or equal to 2 AND less than or equal to 6
x ge 2 AND x le 62 le x le 6
Example 1 Solve each compound inequality and graph the solutions
A 4 le x + 2 le 8
4 le x + 2 AND x + 2 le 8 Write the compound inequality using AND
4 - 2 le x + 2 - 2 x + 2 - 2 le 8 - 2 Subtract 2 from both sides of each simple inequality
2 le x x le 6 Simplify
Graph 2 le x
Graph x le 6
Graph the intersection by finding where the two graphs overlap
B -5 le 2x + 3 lt 9
-5 - le 2x + 3 - lt 9 - Subtract from each part of the inequality
le 2x lt Simplify
-8 _ le 2x _ lt 6 _ Divide each part of the inequality by
le x lt Simplify
Graph -4 le x
Graph x lt 3
Graph the intersection by finding where the two graphs overlap -1 0 1 2 3 4 5-5-4 -3 -2
0 2 4 6 8 10 12-8-6-4 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 82 Lesson 5
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Reflect
2 Discussion Explain why 2 le x le 6 can be considered the short method for writing the AND compound inequality x ge 2 AND x le 6
YourTurn
Solve each compound inequality and graph the solutions
3 -2 lt x - 3 lt 5
4 -10 lt 3x + 2 le 8
Explain 2 Solving Compound Inequalities Involving ORThe graph of a compound inequality involving OR is the union or the combined region of the simple inequality graphs
Compound Inequalities OR
Words Algebra Graph
All real numbers less than 2OR greater than 6
x lt 2 OR x gt 6
All real numbers less than or equal to 2OR greater than or equal to 6
x le 2 OR x ge 6
-1 0 1 2 3 4 5-5-4 -3 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 83 Lesson 5
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oug
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Example 2 Solve each compound inequality and graph the solutions
A -4 + x gt 1 OR -4 + x lt -3
-4 + x gt 1 OR -4 + x lt -3 Write the compound inequality using OR
-4 + 4 + x gt 1 + 4 -4 + 4 + x lt -3 + 4 Add 4 to both sides of each simple inequality
x gt 5 x lt 1 Simplify
Graph x gt 5
Graph x lt 1
Graph the union by combining the graphs
B 2x le 6 OR 3x gt 12
2x le 6 OR 3x gt 12 Write the compound inequality using OR
2x _ le 6 _ OR 3x _ gt 12 _ Divide the first simple inequality by
x le OR x gt
Graph x le 3
Graph x gt 4
Graph the union by combining the graphs
Reflect
5 Critical Thinking What kind of compound inequality has no solution
Divide the second simple inequality by
Simplify
0 1 2 3 4 5 6-4 -3 -2 -1
-0 1 2 3 4 5 6-4 -3 -2 -1
Module 2 84 Lesson 5
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Your Turn
Solve each compound inequality and graph the solutions
6 x - 5 ge -2 OR x -5 le -6
7 4x -1 lt 15 OR 8x ge 48
Explain 3 Creating Compound Inequalities From GraphsGiven a number line graph with a solution set graphed you can create a compound inequality to fit the graph
Example 3 Write the compound inequality shown by each graph
A
The shaded portion of the graph is not between two values so the compound inequality involves OR
On the left the graph shows an arrow pointing left from -1 and a solid circle so use le
The inequality is x le -1
On the right the graph shows an arrow pointing right from 7 and a solid circle so use ge
The inequality is x ge 7
The compound inequality is x le -1 OR x ge 7
B
The graph is shaded between the values and so the compound inequality involves AND
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The compound inequality is
-1 0 1 2 3 4 5-5-4 -3 -2
4 5 6 7 8 9 100 1 2 3
2 3 4 5 6 7 8-2 -1 0 1
10 2 3 4 5 6 7 8 9-1
Module 2 85 Lesson 5
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Reflect
8 What is a short method to write the compound inequality x ge 0 AND x lt 6
Your Turn
Write the compound inequality shown by each graph
9
10
Explain 4 Expressing Acceptable Levels with Compound Inequalities
You can express quality-controls levels in real-world problems using compound inequalities
Example 4 Write a compound inequality to represent the indicated quality-control level and graph the solutions
A The recommended pH level for swimming pool water is between 72 and 76 inclusive
Let p be the pH level of swimming pool water
72 is less than or equal to pH level is less than or equal to 76
72 le p le 76
The compound inequality is 72 le p le 76
Graph the solutions
0-10 -8-9 -7-6 -5-4 -3 -2 -1
71 72 73 74 75 76 77 78 79 8070
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 86 Lesson 5
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oug
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B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
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bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
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Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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age C
redits copy
Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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Mif
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Har
cour
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lishi
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Com
pan
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mag
e C
red
its
copy
bik
erid
erlo
nd
onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
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The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
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Is the inequality true
Could Nora buy $6 party favors for all of her guests without going over budget
Reflect
1 Why does an inequality represent Norarsquos budget calculation better than an equation
2 The solution set of an inequality consists of all values that make the statement true Describe the whole dollar amounts that are in the solution set for this situation
Explain 1 Creating and Solving Inequalities Involving the Distributive Property
You may need to use the Distributive Property before you can solve an inequality
Distributive Property If a b and c are real numbers then a(b + c) = ab + ac
The inequality sign must be reversed when multiplying or dividing both sides of an inequality by a negative number
Example 1
A Trina is buying 12 shirts for the drama club She will choose a style for the blank shirts and then pay an additional charge of $275 for each shirt to have the club logo If Trina cannot spend more than $99 how much can she spend on each blank shirt Write and solve an inequality to find the possible cost of each blank shirt
Let s represent the cost of each blank shirt
Write an inequality to represent the situation 12(s + 275) le 99
Use the Distributive Property 12s + 33 le 99
Subtraction Property of Inequality 12s + 33 - 33 le 99 - 33
Simplify 12s le 66
Division Property of Inequality 12s ___ 12 le 66 __ 12
Simplify s le 55
Module 2 74 Lesson 4
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oug
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Mif
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Har
cour
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lishi
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Com
pan
y
Check your answer
Since s le 55 check a smaller number 12(5 + 275) le 99
Trina can order blank shirts that cost $550 or less 93 le 99 true
B Sergio needs to buy gifts for 8 friends He wants to give the same gift to all his friends and he plans to have the gifts wrapped for an additional charge of $150 each If Sergio spends at least $70 he will receive free shipping on his order Write and solve an inequality to determine how much Sergio needs to spend on each gift in order to receive free shipping
Let g be the cost of one gift
Write an inequality to represent the situation ( g + ) ge 70
Use the Distributive Property g + ge 70
Subtraction Property of Inequality g + 12 - ge 70 -
Simplify 8g ge
Division Property of Inequality 8g _
ge 58 _
Simplify g ge
Check your answer
Since g ge 725 check a larger number 8(8 + 150) ge 70
Sergio must spend at least on each gift ge 70
Reflect
3 Discussion Why is the first step in solving the inequality to use the Distributive Property instead of working inside the parentheses
Your Turn
4 Zachary is planning to send a video game to each of his two brothers If he buys the same game for both brothers and pays $475 to ship each game how much can he spend on each game without spending more than $100 Write and solve an inequality for this situation
Solve each inequality
5 4 _ 3 (6x + 9) lt 4 6 -2 ( 1 _ 4 x + 2 ) ge 5
Module 2 75 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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Explain 2 Creating and Solving Inequalities with Variables on Both Sides
Some inequalities have variable terms on both sides of the inequality symbol You can solve these inequalities the same way you solved equations with variables on both sides Use the properties of inequality to collect all the variable terms on one side and all the constant terms on the other side
Example 2
A The Daily Info charges a fee of $650 plus $80 per week to run an ad The Peoplersquos Paper charges $145 per week For how many weeks must an ad run for the total cost at the Daily Info to be less expensive than the cost at the Peoplersquos Paper Let w be the number of weeks the ad runs in the paper
Write an inequality to represent the situation 650 + 80w lt 145w
Subtraction Property of Inequality 650 + 80w - 80w lt 145w - 80w
Simplify 650 lt 65w
Division Property of Inequality 650 _ 65 lt 65w _ 65
Simplify 10 lt w
The total cost at the Daily Info is less than the cost at the Peoplersquos Paper if the ad runs for more than 10 weeks
B The Home Cleaning Company charges $312 to power-wash the siding of a house plus $12 for each window Power Clean charges $36 per window and the price includes power-washing the siding How many windows must a house have to make the total cost from The Home Cleaning Company less expensive than Power Clean Let w be the number of windows
Write an inequality to represent the situation +12w lt 36w
Subtraction Property of Inequality 312 + 12w - lt 36w -
Simplify 312 lt
Division Property of Inequality 312 _ lt 24w _
Simplify lt w
A house must have more than 13 windows for The Home Cleaning Company to be less expensive than Power Clean
Reflect
7 How would the final inequality change if you divided by ndash24 in the next to last step
Your Turn
8 The school band will sell pizzas to raise money for new uniforms The supplier charges $100 plus $4 per pizza The band members sell the pizzas for $7 each Write and solve an inequality to find how many pizzas the band members will have to sell to make a profit
Module 2 76 Lesson 4
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Elaborate
9 Which inequality symbol would you use to represent the following words or phrases Can you come up with more examples
a at most b farther than c younger than d up to
10 Discussion How are the steps to solving an inequality similar to those for solving an equation How are they different
11 Essential Question Check-In How can you write an inequality that represents a real-world situation
Write an inequality that represents the description and then solve
1 Max has more than 5 carrots (number of carrots Max has = c)
2 Brigitte is shorter than 5 feet (Brigittersquos height = h)
3 Twice a number (x) is less than 10 4 Six more than five times a number (x) is at least twenty-one
5 Dave has $15 to spend on an $8 book and two birthday cards (c) for his friends How much can he spend on each card if he buys the same card for each friend
6 Toni can carry up to 18 lb in her backpack Her lunch weighs 1 lb her gym clothes weigh 2 lb and her books (b) weigh 3 lb each How many books can she carry in her backpack
Evaluate Homework and Practice
bull Online Homeworkbull Hints and Helpbull Extra Practice
Module 2 77 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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pany
Solve each inequality
7 3 (x - 2) gt -3 8 5 + 5 (x + 4) le 20 9 3 + 1 _ 2 (3 - x) lt -7
10 3 (x + 6) - 2 (x + 2) ge 10 11 5 (3 - x) -4 (2 - 3x) gt 2 12 1 _ 2 (4x - 2) - 2 _ 3 (6x + 9) le 4
13 x + 1 gt -5 (7 - 2x) 14 5 _ 3 (6x + 3) le 2x - 7
15 2x le - 2 __ 3 (4x + 4) 16 1 __ 2 (-2x - 10) gt 3 (4 - 6x)
17 -5 - 3x ge 2 (10 + 2x) + 3 18 -3 (9x + 20) ge 15x - 20
19 8 ( 1 _ 4 x - 3) + 24 lt 4 ( x + 5 ) 20 6x - 2 (x + 2) gt 2 - 3 (x + 3)
Module 2 78 Lesson 4
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21 Physics A crane cable can support a maximum load of 15000 kg If a bucket has a mass of 2000 kg and gravel has a mass of 1500 kg for every cubic meter how many cubic meters of gravel (g) can be safely lifted by the crane
22 Find the solution set of each inequality below and then determine which inequalities have the same solution set as 1 _ 3 ( -5x - 3 ) lt 14
a 1 _ 3 (5x + 3) gt -14 b 2 _ 5 (10x + 20) gt 44
c - 2 _ 5 (10x + 20) lt -44 d - 1 _ 3 (5x + 3) lt 14
e 2 _ 5 (10x - 20) gt -44 f 1 _ 3 (5x + 3) lt -14
HOT Focus on Higher Order Thinking
23 Explain the Error Sven is trying to find the maximum amount of time he can spend practicing the five scales of piano music he is supposed to be working on He has 60 minutes to practice piano and would like to spend at least 35 minutes playing songs instead of practicing scales So Sven sets up the following inequality where t is the number of minutes he spends on each scale and solves it
60 - 5t le 35-5t le -25
t ge 5
Sven has concluded that he should spend 5 minutes or more on each scale Is this correct If not what mistake did he make Then solve for the correct answer
Module 2 79 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
24 Critical Thinking Anika wants to determine the maximum number of tulip bulbs (t) she can purchase if each bulb costs $150 She will also need to purchase separate pots for each bulb at $125 each and a bag of potting soil for $1000 Set up an inequality to determine how many tulip bulbs Anika can purchase without spending more than $2000 and solve it Can Anika buy exactly enough bulbs and pots to spend the full $2000 Explain Can you think of a better inequality to describe the answer
25 Geometry The area of the triangle shown is no more than 10 square inches
a Write an inequality that can be used to find x
b Solve the inequality from part a c What is the maximum height of the triangle
Lesson Performance TaskWhen planning an airplane route the trip planner must be careful to consider the range the aircraft can travel and the availability of airports to stop and refuel
A large commercial jet airplane burns approximately 5 gallons of fuel per mile flown plus about 8500 gallons of fuel per trip to reach cruising altitude With a useable fuel capacity of 50000 gallons (there is additional fuel reserved for emergencies) describe the acceptable distance for which an airline could establish a non-stop flight
For flights originating from Chicago determine which cities could be safely reached by a non-stop flight
City Distance from Chicago (miles)
Bangalore India 8530
Jakarta Indonesia 9810
Johannesburg South Africa 8680
Moscow Russia 4970
Paris France 4130
Perth Australia 10970
Tokyo Japan 6300
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oug
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eva O
lesiaShutterstock
(2x - 3) in
4 in
Module 2 80 Lesson 4
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Name Class Date
Resource Locker
Explore Truth Tables and Compound StatementsA compound statement is formed by combining two or more simple statements A compound statement can be true or false A compound statement involving AND is true when both simple statements are true A compound statement involving OR is true when either one simple statement or both are true
A Complete the truth table
P QP
True or FalseQ
True or FalseP AND Q
True or False
A dog is a mammal Red is a color
A dog is a mammal Red is not a color
A dog is a fish Red is a color
A dog is a fish Red is not a color
B P AND Q is true when
C Complete the truth table
P QP
True or FalseQ
True or FalseP OR Q
True or False
1 is an odd number 2 is an even number
1 is an odd number 2 is an odd number
1 is an even number 2 is an even number
1 is an even number 2 is an odd number
D P OR Q is true when
Reflect
1 Give two simple statements P and Q for which P AND Q is false and P OR Q is true
Module 2 81 Lesson 5
25 Creating and Solving Compound Inequalities
Essential Question How can you solve a compound inequality and graph the solution set
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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Explain 1 Solving Compound Inequalities Involving ANDCombining two or more simple inequalities forms a compound inequality The graph of a compound inequality involving AND is the intersection or the overlapping region of the simple inequality graphs
Compound Inequalities AND
Words Algebra Graph
All real numbers greater than 2AND less than 6
x gt 2 AND x lt 62 lt x lt 6
All real numbers greater than or equal to 2 AND less than or equal to 6
x ge 2 AND x le 62 le x le 6
Example 1 Solve each compound inequality and graph the solutions
A 4 le x + 2 le 8
4 le x + 2 AND x + 2 le 8 Write the compound inequality using AND
4 - 2 le x + 2 - 2 x + 2 - 2 le 8 - 2 Subtract 2 from both sides of each simple inequality
2 le x x le 6 Simplify
Graph 2 le x
Graph x le 6
Graph the intersection by finding where the two graphs overlap
B -5 le 2x + 3 lt 9
-5 - le 2x + 3 - lt 9 - Subtract from each part of the inequality
le 2x lt Simplify
-8 _ le 2x _ lt 6 _ Divide each part of the inequality by
le x lt Simplify
Graph -4 le x
Graph x lt 3
Graph the intersection by finding where the two graphs overlap -1 0 1 2 3 4 5-5-4 -3 -2
0 2 4 6 8 10 12-8-6-4 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 82 Lesson 5
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Reflect
2 Discussion Explain why 2 le x le 6 can be considered the short method for writing the AND compound inequality x ge 2 AND x le 6
YourTurn
Solve each compound inequality and graph the solutions
3 -2 lt x - 3 lt 5
4 -10 lt 3x + 2 le 8
Explain 2 Solving Compound Inequalities Involving ORThe graph of a compound inequality involving OR is the union or the combined region of the simple inequality graphs
Compound Inequalities OR
Words Algebra Graph
All real numbers less than 2OR greater than 6
x lt 2 OR x gt 6
All real numbers less than or equal to 2OR greater than or equal to 6
x le 2 OR x ge 6
-1 0 1 2 3 4 5-5-4 -3 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 83 Lesson 5
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oug
hton Mifflin H
arcourt Publishin
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pany
Example 2 Solve each compound inequality and graph the solutions
A -4 + x gt 1 OR -4 + x lt -3
-4 + x gt 1 OR -4 + x lt -3 Write the compound inequality using OR
-4 + 4 + x gt 1 + 4 -4 + 4 + x lt -3 + 4 Add 4 to both sides of each simple inequality
x gt 5 x lt 1 Simplify
Graph x gt 5
Graph x lt 1
Graph the union by combining the graphs
B 2x le 6 OR 3x gt 12
2x le 6 OR 3x gt 12 Write the compound inequality using OR
2x _ le 6 _ OR 3x _ gt 12 _ Divide the first simple inequality by
x le OR x gt
Graph x le 3
Graph x gt 4
Graph the union by combining the graphs
Reflect
5 Critical Thinking What kind of compound inequality has no solution
Divide the second simple inequality by
Simplify
0 1 2 3 4 5 6-4 -3 -2 -1
-0 1 2 3 4 5 6-4 -3 -2 -1
Module 2 84 Lesson 5
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oug
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pan
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Your Turn
Solve each compound inequality and graph the solutions
6 x - 5 ge -2 OR x -5 le -6
7 4x -1 lt 15 OR 8x ge 48
Explain 3 Creating Compound Inequalities From GraphsGiven a number line graph with a solution set graphed you can create a compound inequality to fit the graph
Example 3 Write the compound inequality shown by each graph
A
The shaded portion of the graph is not between two values so the compound inequality involves OR
On the left the graph shows an arrow pointing left from -1 and a solid circle so use le
The inequality is x le -1
On the right the graph shows an arrow pointing right from 7 and a solid circle so use ge
The inequality is x ge 7
The compound inequality is x le -1 OR x ge 7
B
The graph is shaded between the values and so the compound inequality involves AND
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The compound inequality is
-1 0 1 2 3 4 5-5-4 -3 -2
4 5 6 7 8 9 100 1 2 3
2 3 4 5 6 7 8-2 -1 0 1
10 2 3 4 5 6 7 8 9-1
Module 2 85 Lesson 5
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oug
hton Mifflin H
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pany
Reflect
8 What is a short method to write the compound inequality x ge 0 AND x lt 6
Your Turn
Write the compound inequality shown by each graph
9
10
Explain 4 Expressing Acceptable Levels with Compound Inequalities
You can express quality-controls levels in real-world problems using compound inequalities
Example 4 Write a compound inequality to represent the indicated quality-control level and graph the solutions
A The recommended pH level for swimming pool water is between 72 and 76 inclusive
Let p be the pH level of swimming pool water
72 is less than or equal to pH level is less than or equal to 76
72 le p le 76
The compound inequality is 72 le p le 76
Graph the solutions
0-10 -8-9 -7-6 -5-4 -3 -2 -1
71 72 73 74 75 76 77 78 79 8070
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 86 Lesson 5
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oug
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pan
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B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
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oug
hton Mifflin H
arcourt Publishin
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pany
bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
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oug
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cour
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Com
pan
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Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
arcourt Publishin
g Com
pany bull Im
age C
redits copy
Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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Mif
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Har
cour
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lishi
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Com
pan
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mag
e C
red
its
copy
bik
erid
erlo
nd
onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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pany
The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
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cour
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Com
pan
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Check your answer
Since s le 55 check a smaller number 12(5 + 275) le 99
Trina can order blank shirts that cost $550 or less 93 le 99 true
B Sergio needs to buy gifts for 8 friends He wants to give the same gift to all his friends and he plans to have the gifts wrapped for an additional charge of $150 each If Sergio spends at least $70 he will receive free shipping on his order Write and solve an inequality to determine how much Sergio needs to spend on each gift in order to receive free shipping
Let g be the cost of one gift
Write an inequality to represent the situation ( g + ) ge 70
Use the Distributive Property g + ge 70
Subtraction Property of Inequality g + 12 - ge 70 -
Simplify 8g ge
Division Property of Inequality 8g _
ge 58 _
Simplify g ge
Check your answer
Since g ge 725 check a larger number 8(8 + 150) ge 70
Sergio must spend at least on each gift ge 70
Reflect
3 Discussion Why is the first step in solving the inequality to use the Distributive Property instead of working inside the parentheses
Your Turn
4 Zachary is planning to send a video game to each of his two brothers If he buys the same game for both brothers and pays $475 to ship each game how much can he spend on each game without spending more than $100 Write and solve an inequality for this situation
Solve each inequality
5 4 _ 3 (6x + 9) lt 4 6 -2 ( 1 _ 4 x + 2 ) ge 5
Module 2 75 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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arcourt Publishin
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pany
Explain 2 Creating and Solving Inequalities with Variables on Both Sides
Some inequalities have variable terms on both sides of the inequality symbol You can solve these inequalities the same way you solved equations with variables on both sides Use the properties of inequality to collect all the variable terms on one side and all the constant terms on the other side
Example 2
A The Daily Info charges a fee of $650 plus $80 per week to run an ad The Peoplersquos Paper charges $145 per week For how many weeks must an ad run for the total cost at the Daily Info to be less expensive than the cost at the Peoplersquos Paper Let w be the number of weeks the ad runs in the paper
Write an inequality to represent the situation 650 + 80w lt 145w
Subtraction Property of Inequality 650 + 80w - 80w lt 145w - 80w
Simplify 650 lt 65w
Division Property of Inequality 650 _ 65 lt 65w _ 65
Simplify 10 lt w
The total cost at the Daily Info is less than the cost at the Peoplersquos Paper if the ad runs for more than 10 weeks
B The Home Cleaning Company charges $312 to power-wash the siding of a house plus $12 for each window Power Clean charges $36 per window and the price includes power-washing the siding How many windows must a house have to make the total cost from The Home Cleaning Company less expensive than Power Clean Let w be the number of windows
Write an inequality to represent the situation +12w lt 36w
Subtraction Property of Inequality 312 + 12w - lt 36w -
Simplify 312 lt
Division Property of Inequality 312 _ lt 24w _
Simplify lt w
A house must have more than 13 windows for The Home Cleaning Company to be less expensive than Power Clean
Reflect
7 How would the final inequality change if you divided by ndash24 in the next to last step
Your Turn
8 The school band will sell pizzas to raise money for new uniforms The supplier charges $100 plus $4 per pizza The band members sell the pizzas for $7 each Write and solve an inequality to find how many pizzas the band members will have to sell to make a profit
Module 2 76 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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oug
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cour
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pan
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Elaborate
9 Which inequality symbol would you use to represent the following words or phrases Can you come up with more examples
a at most b farther than c younger than d up to
10 Discussion How are the steps to solving an inequality similar to those for solving an equation How are they different
11 Essential Question Check-In How can you write an inequality that represents a real-world situation
Write an inequality that represents the description and then solve
1 Max has more than 5 carrots (number of carrots Max has = c)
2 Brigitte is shorter than 5 feet (Brigittersquos height = h)
3 Twice a number (x) is less than 10 4 Six more than five times a number (x) is at least twenty-one
5 Dave has $15 to spend on an $8 book and two birthday cards (c) for his friends How much can he spend on each card if he buys the same card for each friend
6 Toni can carry up to 18 lb in her backpack Her lunch weighs 1 lb her gym clothes weigh 2 lb and her books (b) weigh 3 lb each How many books can she carry in her backpack
Evaluate Homework and Practice
bull Online Homeworkbull Hints and Helpbull Extra Practice
Module 2 77 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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oug
hton Mifflin H
arcourt Publishin
g Com
pany
Solve each inequality
7 3 (x - 2) gt -3 8 5 + 5 (x + 4) le 20 9 3 + 1 _ 2 (3 - x) lt -7
10 3 (x + 6) - 2 (x + 2) ge 10 11 5 (3 - x) -4 (2 - 3x) gt 2 12 1 _ 2 (4x - 2) - 2 _ 3 (6x + 9) le 4
13 x + 1 gt -5 (7 - 2x) 14 5 _ 3 (6x + 3) le 2x - 7
15 2x le - 2 __ 3 (4x + 4) 16 1 __ 2 (-2x - 10) gt 3 (4 - 6x)
17 -5 - 3x ge 2 (10 + 2x) + 3 18 -3 (9x + 20) ge 15x - 20
19 8 ( 1 _ 4 x - 3) + 24 lt 4 ( x + 5 ) 20 6x - 2 (x + 2) gt 2 - 3 (x + 3)
Module 2 78 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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Mif
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cour
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lishi
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Com
pan
y
21 Physics A crane cable can support a maximum load of 15000 kg If a bucket has a mass of 2000 kg and gravel has a mass of 1500 kg for every cubic meter how many cubic meters of gravel (g) can be safely lifted by the crane
22 Find the solution set of each inequality below and then determine which inequalities have the same solution set as 1 _ 3 ( -5x - 3 ) lt 14
a 1 _ 3 (5x + 3) gt -14 b 2 _ 5 (10x + 20) gt 44
c - 2 _ 5 (10x + 20) lt -44 d - 1 _ 3 (5x + 3) lt 14
e 2 _ 5 (10x - 20) gt -44 f 1 _ 3 (5x + 3) lt -14
HOT Focus on Higher Order Thinking
23 Explain the Error Sven is trying to find the maximum amount of time he can spend practicing the five scales of piano music he is supposed to be working on He has 60 minutes to practice piano and would like to spend at least 35 minutes playing songs instead of practicing scales So Sven sets up the following inequality where t is the number of minutes he spends on each scale and solves it
60 - 5t le 35-5t le -25
t ge 5
Sven has concluded that he should spend 5 minutes or more on each scale Is this correct If not what mistake did he make Then solve for the correct answer
Module 2 79 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
24 Critical Thinking Anika wants to determine the maximum number of tulip bulbs (t) she can purchase if each bulb costs $150 She will also need to purchase separate pots for each bulb at $125 each and a bag of potting soil for $1000 Set up an inequality to determine how many tulip bulbs Anika can purchase without spending more than $2000 and solve it Can Anika buy exactly enough bulbs and pots to spend the full $2000 Explain Can you think of a better inequality to describe the answer
25 Geometry The area of the triangle shown is no more than 10 square inches
a Write an inequality that can be used to find x
b Solve the inequality from part a c What is the maximum height of the triangle
Lesson Performance TaskWhen planning an airplane route the trip planner must be careful to consider the range the aircraft can travel and the availability of airports to stop and refuel
A large commercial jet airplane burns approximately 5 gallons of fuel per mile flown plus about 8500 gallons of fuel per trip to reach cruising altitude With a useable fuel capacity of 50000 gallons (there is additional fuel reserved for emergencies) describe the acceptable distance for which an airline could establish a non-stop flight
For flights originating from Chicago determine which cities could be safely reached by a non-stop flight
City Distance from Chicago (miles)
Bangalore India 8530
Jakarta Indonesia 9810
Johannesburg South Africa 8680
Moscow Russia 4970
Paris France 4130
Perth Australia 10970
Tokyo Japan 6300
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany bull Im
age cred
its copySarych
eva O
lesiaShutterstock
(2x - 3) in
4 in
Module 2 80 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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Har
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Name Class Date
Resource Locker
Explore Truth Tables and Compound StatementsA compound statement is formed by combining two or more simple statements A compound statement can be true or false A compound statement involving AND is true when both simple statements are true A compound statement involving OR is true when either one simple statement or both are true
A Complete the truth table
P QP
True or FalseQ
True or FalseP AND Q
True or False
A dog is a mammal Red is a color
A dog is a mammal Red is not a color
A dog is a fish Red is a color
A dog is a fish Red is not a color
B P AND Q is true when
C Complete the truth table
P QP
True or FalseQ
True or FalseP OR Q
True or False
1 is an odd number 2 is an even number
1 is an odd number 2 is an odd number
1 is an even number 2 is an even number
1 is an even number 2 is an odd number
D P OR Q is true when
Reflect
1 Give two simple statements P and Q for which P AND Q is false and P OR Q is true
Module 2 81 Lesson 5
25 Creating and Solving Compound Inequalities
Essential Question How can you solve a compound inequality and graph the solution set
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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Explain 1 Solving Compound Inequalities Involving ANDCombining two or more simple inequalities forms a compound inequality The graph of a compound inequality involving AND is the intersection or the overlapping region of the simple inequality graphs
Compound Inequalities AND
Words Algebra Graph
All real numbers greater than 2AND less than 6
x gt 2 AND x lt 62 lt x lt 6
All real numbers greater than or equal to 2 AND less than or equal to 6
x ge 2 AND x le 62 le x le 6
Example 1 Solve each compound inequality and graph the solutions
A 4 le x + 2 le 8
4 le x + 2 AND x + 2 le 8 Write the compound inequality using AND
4 - 2 le x + 2 - 2 x + 2 - 2 le 8 - 2 Subtract 2 from both sides of each simple inequality
2 le x x le 6 Simplify
Graph 2 le x
Graph x le 6
Graph the intersection by finding where the two graphs overlap
B -5 le 2x + 3 lt 9
-5 - le 2x + 3 - lt 9 - Subtract from each part of the inequality
le 2x lt Simplify
-8 _ le 2x _ lt 6 _ Divide each part of the inequality by
le x lt Simplify
Graph -4 le x
Graph x lt 3
Graph the intersection by finding where the two graphs overlap -1 0 1 2 3 4 5-5-4 -3 -2
0 2 4 6 8 10 12-8-6-4 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 82 Lesson 5
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Reflect
2 Discussion Explain why 2 le x le 6 can be considered the short method for writing the AND compound inequality x ge 2 AND x le 6
YourTurn
Solve each compound inequality and graph the solutions
3 -2 lt x - 3 lt 5
4 -10 lt 3x + 2 le 8
Explain 2 Solving Compound Inequalities Involving ORThe graph of a compound inequality involving OR is the union or the combined region of the simple inequality graphs
Compound Inequalities OR
Words Algebra Graph
All real numbers less than 2OR greater than 6
x lt 2 OR x gt 6
All real numbers less than or equal to 2OR greater than or equal to 6
x le 2 OR x ge 6
-1 0 1 2 3 4 5-5-4 -3 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 83 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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Example 2 Solve each compound inequality and graph the solutions
A -4 + x gt 1 OR -4 + x lt -3
-4 + x gt 1 OR -4 + x lt -3 Write the compound inequality using OR
-4 + 4 + x gt 1 + 4 -4 + 4 + x lt -3 + 4 Add 4 to both sides of each simple inequality
x gt 5 x lt 1 Simplify
Graph x gt 5
Graph x lt 1
Graph the union by combining the graphs
B 2x le 6 OR 3x gt 12
2x le 6 OR 3x gt 12 Write the compound inequality using OR
2x _ le 6 _ OR 3x _ gt 12 _ Divide the first simple inequality by
x le OR x gt
Graph x le 3
Graph x gt 4
Graph the union by combining the graphs
Reflect
5 Critical Thinking What kind of compound inequality has no solution
Divide the second simple inequality by
Simplify
0 1 2 3 4 5 6-4 -3 -2 -1
-0 1 2 3 4 5 6-4 -3 -2 -1
Module 2 84 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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oug
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cour
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Your Turn
Solve each compound inequality and graph the solutions
6 x - 5 ge -2 OR x -5 le -6
7 4x -1 lt 15 OR 8x ge 48
Explain 3 Creating Compound Inequalities From GraphsGiven a number line graph with a solution set graphed you can create a compound inequality to fit the graph
Example 3 Write the compound inequality shown by each graph
A
The shaded portion of the graph is not between two values so the compound inequality involves OR
On the left the graph shows an arrow pointing left from -1 and a solid circle so use le
The inequality is x le -1
On the right the graph shows an arrow pointing right from 7 and a solid circle so use ge
The inequality is x ge 7
The compound inequality is x le -1 OR x ge 7
B
The graph is shaded between the values and so the compound inequality involves AND
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The compound inequality is
-1 0 1 2 3 4 5-5-4 -3 -2
4 5 6 7 8 9 100 1 2 3
2 3 4 5 6 7 8-2 -1 0 1
10 2 3 4 5 6 7 8 9-1
Module 2 85 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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oug
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Reflect
8 What is a short method to write the compound inequality x ge 0 AND x lt 6
Your Turn
Write the compound inequality shown by each graph
9
10
Explain 4 Expressing Acceptable Levels with Compound Inequalities
You can express quality-controls levels in real-world problems using compound inequalities
Example 4 Write a compound inequality to represent the indicated quality-control level and graph the solutions
A The recommended pH level for swimming pool water is between 72 and 76 inclusive
Let p be the pH level of swimming pool water
72 is less than or equal to pH level is less than or equal to 76
72 le p le 76
The compound inequality is 72 le p le 76
Graph the solutions
0-10 -8-9 -7-6 -5-4 -3 -2 -1
71 72 73 74 75 76 77 78 79 8070
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 86 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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oug
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pan
y
B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
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pany
bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
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oug
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Har
cour
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Com
pan
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Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
arcourt Publishin
g Com
pany bull Im
age C
redits copy
Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
hton
Mif
flin
Har
cour
t Pub
lishi
ng
Com
pan
y bull I
mag
e C
red
its
copy
bik
erid
erlo
nd
onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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Explain 2 Creating and Solving Inequalities with Variables on Both Sides
Some inequalities have variable terms on both sides of the inequality symbol You can solve these inequalities the same way you solved equations with variables on both sides Use the properties of inequality to collect all the variable terms on one side and all the constant terms on the other side
Example 2
A The Daily Info charges a fee of $650 plus $80 per week to run an ad The Peoplersquos Paper charges $145 per week For how many weeks must an ad run for the total cost at the Daily Info to be less expensive than the cost at the Peoplersquos Paper Let w be the number of weeks the ad runs in the paper
Write an inequality to represent the situation 650 + 80w lt 145w
Subtraction Property of Inequality 650 + 80w - 80w lt 145w - 80w
Simplify 650 lt 65w
Division Property of Inequality 650 _ 65 lt 65w _ 65
Simplify 10 lt w
The total cost at the Daily Info is less than the cost at the Peoplersquos Paper if the ad runs for more than 10 weeks
B The Home Cleaning Company charges $312 to power-wash the siding of a house plus $12 for each window Power Clean charges $36 per window and the price includes power-washing the siding How many windows must a house have to make the total cost from The Home Cleaning Company less expensive than Power Clean Let w be the number of windows
Write an inequality to represent the situation +12w lt 36w
Subtraction Property of Inequality 312 + 12w - lt 36w -
Simplify 312 lt
Division Property of Inequality 312 _ lt 24w _
Simplify lt w
A house must have more than 13 windows for The Home Cleaning Company to be less expensive than Power Clean
Reflect
7 How would the final inequality change if you divided by ndash24 in the next to last step
Your Turn
8 The school band will sell pizzas to raise money for new uniforms The supplier charges $100 plus $4 per pizza The band members sell the pizzas for $7 each Write and solve an inequality to find how many pizzas the band members will have to sell to make a profit
Module 2 76 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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oug
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cour
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Elaborate
9 Which inequality symbol would you use to represent the following words or phrases Can you come up with more examples
a at most b farther than c younger than d up to
10 Discussion How are the steps to solving an inequality similar to those for solving an equation How are they different
11 Essential Question Check-In How can you write an inequality that represents a real-world situation
Write an inequality that represents the description and then solve
1 Max has more than 5 carrots (number of carrots Max has = c)
2 Brigitte is shorter than 5 feet (Brigittersquos height = h)
3 Twice a number (x) is less than 10 4 Six more than five times a number (x) is at least twenty-one
5 Dave has $15 to spend on an $8 book and two birthday cards (c) for his friends How much can he spend on each card if he buys the same card for each friend
6 Toni can carry up to 18 lb in her backpack Her lunch weighs 1 lb her gym clothes weigh 2 lb and her books (b) weigh 3 lb each How many books can she carry in her backpack
Evaluate Homework and Practice
bull Online Homeworkbull Hints and Helpbull Extra Practice
Module 2 77 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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pany
Solve each inequality
7 3 (x - 2) gt -3 8 5 + 5 (x + 4) le 20 9 3 + 1 _ 2 (3 - x) lt -7
10 3 (x + 6) - 2 (x + 2) ge 10 11 5 (3 - x) -4 (2 - 3x) gt 2 12 1 _ 2 (4x - 2) - 2 _ 3 (6x + 9) le 4
13 x + 1 gt -5 (7 - 2x) 14 5 _ 3 (6x + 3) le 2x - 7
15 2x le - 2 __ 3 (4x + 4) 16 1 __ 2 (-2x - 10) gt 3 (4 - 6x)
17 -5 - 3x ge 2 (10 + 2x) + 3 18 -3 (9x + 20) ge 15x - 20
19 8 ( 1 _ 4 x - 3) + 24 lt 4 ( x + 5 ) 20 6x - 2 (x + 2) gt 2 - 3 (x + 3)
Module 2 78 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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Har
cour
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pan
y
21 Physics A crane cable can support a maximum load of 15000 kg If a bucket has a mass of 2000 kg and gravel has a mass of 1500 kg for every cubic meter how many cubic meters of gravel (g) can be safely lifted by the crane
22 Find the solution set of each inequality below and then determine which inequalities have the same solution set as 1 _ 3 ( -5x - 3 ) lt 14
a 1 _ 3 (5x + 3) gt -14 b 2 _ 5 (10x + 20) gt 44
c - 2 _ 5 (10x + 20) lt -44 d - 1 _ 3 (5x + 3) lt 14
e 2 _ 5 (10x - 20) gt -44 f 1 _ 3 (5x + 3) lt -14
HOT Focus on Higher Order Thinking
23 Explain the Error Sven is trying to find the maximum amount of time he can spend practicing the five scales of piano music he is supposed to be working on He has 60 minutes to practice piano and would like to spend at least 35 minutes playing songs instead of practicing scales So Sven sets up the following inequality where t is the number of minutes he spends on each scale and solves it
60 - 5t le 35-5t le -25
t ge 5
Sven has concluded that he should spend 5 minutes or more on each scale Is this correct If not what mistake did he make Then solve for the correct answer
Module 2 79 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
24 Critical Thinking Anika wants to determine the maximum number of tulip bulbs (t) she can purchase if each bulb costs $150 She will also need to purchase separate pots for each bulb at $125 each and a bag of potting soil for $1000 Set up an inequality to determine how many tulip bulbs Anika can purchase without spending more than $2000 and solve it Can Anika buy exactly enough bulbs and pots to spend the full $2000 Explain Can you think of a better inequality to describe the answer
25 Geometry The area of the triangle shown is no more than 10 square inches
a Write an inequality that can be used to find x
b Solve the inequality from part a c What is the maximum height of the triangle
Lesson Performance TaskWhen planning an airplane route the trip planner must be careful to consider the range the aircraft can travel and the availability of airports to stop and refuel
A large commercial jet airplane burns approximately 5 gallons of fuel per mile flown plus about 8500 gallons of fuel per trip to reach cruising altitude With a useable fuel capacity of 50000 gallons (there is additional fuel reserved for emergencies) describe the acceptable distance for which an airline could establish a non-stop flight
For flights originating from Chicago determine which cities could be safely reached by a non-stop flight
City Distance from Chicago (miles)
Bangalore India 8530
Jakarta Indonesia 9810
Johannesburg South Africa 8680
Moscow Russia 4970
Paris France 4130
Perth Australia 10970
Tokyo Japan 6300
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany bull Im
age cred
its copySarych
eva O
lesiaShutterstock
(2x - 3) in
4 in
Module 2 80 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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Mif
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Har
cour
t Pub
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Com
pan
y
Name Class Date
Resource Locker
Explore Truth Tables and Compound StatementsA compound statement is formed by combining two or more simple statements A compound statement can be true or false A compound statement involving AND is true when both simple statements are true A compound statement involving OR is true when either one simple statement or both are true
A Complete the truth table
P QP
True or FalseQ
True or FalseP AND Q
True or False
A dog is a mammal Red is a color
A dog is a mammal Red is not a color
A dog is a fish Red is a color
A dog is a fish Red is not a color
B P AND Q is true when
C Complete the truth table
P QP
True or FalseQ
True or FalseP OR Q
True or False
1 is an odd number 2 is an even number
1 is an odd number 2 is an odd number
1 is an even number 2 is an even number
1 is an even number 2 is an odd number
D P OR Q is true when
Reflect
1 Give two simple statements P and Q for which P AND Q is false and P OR Q is true
Module 2 81 Lesson 5
25 Creating and Solving Compound Inequalities
Essential Question How can you solve a compound inequality and graph the solution set
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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arcourt Publishin
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pany
Explain 1 Solving Compound Inequalities Involving ANDCombining two or more simple inequalities forms a compound inequality The graph of a compound inequality involving AND is the intersection or the overlapping region of the simple inequality graphs
Compound Inequalities AND
Words Algebra Graph
All real numbers greater than 2AND less than 6
x gt 2 AND x lt 62 lt x lt 6
All real numbers greater than or equal to 2 AND less than or equal to 6
x ge 2 AND x le 62 le x le 6
Example 1 Solve each compound inequality and graph the solutions
A 4 le x + 2 le 8
4 le x + 2 AND x + 2 le 8 Write the compound inequality using AND
4 - 2 le x + 2 - 2 x + 2 - 2 le 8 - 2 Subtract 2 from both sides of each simple inequality
2 le x x le 6 Simplify
Graph 2 le x
Graph x le 6
Graph the intersection by finding where the two graphs overlap
B -5 le 2x + 3 lt 9
-5 - le 2x + 3 - lt 9 - Subtract from each part of the inequality
le 2x lt Simplify
-8 _ le 2x _ lt 6 _ Divide each part of the inequality by
le x lt Simplify
Graph -4 le x
Graph x lt 3
Graph the intersection by finding where the two graphs overlap -1 0 1 2 3 4 5-5-4 -3 -2
0 2 4 6 8 10 12-8-6-4 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 82 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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oug
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Mif
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Har
cour
t Pub
lishi
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Com
pan
y
Reflect
2 Discussion Explain why 2 le x le 6 can be considered the short method for writing the AND compound inequality x ge 2 AND x le 6
YourTurn
Solve each compound inequality and graph the solutions
3 -2 lt x - 3 lt 5
4 -10 lt 3x + 2 le 8
Explain 2 Solving Compound Inequalities Involving ORThe graph of a compound inequality involving OR is the union or the combined region of the simple inequality graphs
Compound Inequalities OR
Words Algebra Graph
All real numbers less than 2OR greater than 6
x lt 2 OR x gt 6
All real numbers less than or equal to 2OR greater than or equal to 6
x le 2 OR x ge 6
-1 0 1 2 3 4 5-5-4 -3 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 83 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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arcourt Publishin
g Com
pany
Example 2 Solve each compound inequality and graph the solutions
A -4 + x gt 1 OR -4 + x lt -3
-4 + x gt 1 OR -4 + x lt -3 Write the compound inequality using OR
-4 + 4 + x gt 1 + 4 -4 + 4 + x lt -3 + 4 Add 4 to both sides of each simple inequality
x gt 5 x lt 1 Simplify
Graph x gt 5
Graph x lt 1
Graph the union by combining the graphs
B 2x le 6 OR 3x gt 12
2x le 6 OR 3x gt 12 Write the compound inequality using OR
2x _ le 6 _ OR 3x _ gt 12 _ Divide the first simple inequality by
x le OR x gt
Graph x le 3
Graph x gt 4
Graph the union by combining the graphs
Reflect
5 Critical Thinking What kind of compound inequality has no solution
Divide the second simple inequality by
Simplify
0 1 2 3 4 5 6-4 -3 -2 -1
-0 1 2 3 4 5 6-4 -3 -2 -1
Module 2 84 Lesson 5
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oug
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Your Turn
Solve each compound inequality and graph the solutions
6 x - 5 ge -2 OR x -5 le -6
7 4x -1 lt 15 OR 8x ge 48
Explain 3 Creating Compound Inequalities From GraphsGiven a number line graph with a solution set graphed you can create a compound inequality to fit the graph
Example 3 Write the compound inequality shown by each graph
A
The shaded portion of the graph is not between two values so the compound inequality involves OR
On the left the graph shows an arrow pointing left from -1 and a solid circle so use le
The inequality is x le -1
On the right the graph shows an arrow pointing right from 7 and a solid circle so use ge
The inequality is x ge 7
The compound inequality is x le -1 OR x ge 7
B
The graph is shaded between the values and so the compound inequality involves AND
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The compound inequality is
-1 0 1 2 3 4 5-5-4 -3 -2
4 5 6 7 8 9 100 1 2 3
2 3 4 5 6 7 8-2 -1 0 1
10 2 3 4 5 6 7 8 9-1
Module 2 85 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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oug
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Reflect
8 What is a short method to write the compound inequality x ge 0 AND x lt 6
Your Turn
Write the compound inequality shown by each graph
9
10
Explain 4 Expressing Acceptable Levels with Compound Inequalities
You can express quality-controls levels in real-world problems using compound inequalities
Example 4 Write a compound inequality to represent the indicated quality-control level and graph the solutions
A The recommended pH level for swimming pool water is between 72 and 76 inclusive
Let p be the pH level of swimming pool water
72 is less than or equal to pH level is less than or equal to 76
72 le p le 76
The compound inequality is 72 le p le 76
Graph the solutions
0-10 -8-9 -7-6 -5-4 -3 -2 -1
71 72 73 74 75 76 77 78 79 8070
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 86 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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oug
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t Pub
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pan
y
B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
arcourt Publishin
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pany
bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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oug
hton
Mif
flin
Har
cour
t Pub
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ng
Com
pan
y
Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
arcourt Publishin
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Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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bik
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nd
onS
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ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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pany
The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
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oug
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Elaborate
9 Which inequality symbol would you use to represent the following words or phrases Can you come up with more examples
a at most b farther than c younger than d up to
10 Discussion How are the steps to solving an inequality similar to those for solving an equation How are they different
11 Essential Question Check-In How can you write an inequality that represents a real-world situation
Write an inequality that represents the description and then solve
1 Max has more than 5 carrots (number of carrots Max has = c)
2 Brigitte is shorter than 5 feet (Brigittersquos height = h)
3 Twice a number (x) is less than 10 4 Six more than five times a number (x) is at least twenty-one
5 Dave has $15 to spend on an $8 book and two birthday cards (c) for his friends How much can he spend on each card if he buys the same card for each friend
6 Toni can carry up to 18 lb in her backpack Her lunch weighs 1 lb her gym clothes weigh 2 lb and her books (b) weigh 3 lb each How many books can she carry in her backpack
Evaluate Homework and Practice
bull Online Homeworkbull Hints and Helpbull Extra Practice
Module 2 77 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquoCorrectionKey=NL-BCA-B
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oug
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arcourt Publishin
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pany
Solve each inequality
7 3 (x - 2) gt -3 8 5 + 5 (x + 4) le 20 9 3 + 1 _ 2 (3 - x) lt -7
10 3 (x + 6) - 2 (x + 2) ge 10 11 5 (3 - x) -4 (2 - 3x) gt 2 12 1 _ 2 (4x - 2) - 2 _ 3 (6x + 9) le 4
13 x + 1 gt -5 (7 - 2x) 14 5 _ 3 (6x + 3) le 2x - 7
15 2x le - 2 __ 3 (4x + 4) 16 1 __ 2 (-2x - 10) gt 3 (4 - 6x)
17 -5 - 3x ge 2 (10 + 2x) + 3 18 -3 (9x + 20) ge 15x - 20
19 8 ( 1 _ 4 x - 3) + 24 lt 4 ( x + 5 ) 20 6x - 2 (x + 2) gt 2 - 3 (x + 3)
Module 2 78 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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21 Physics A crane cable can support a maximum load of 15000 kg If a bucket has a mass of 2000 kg and gravel has a mass of 1500 kg for every cubic meter how many cubic meters of gravel (g) can be safely lifted by the crane
22 Find the solution set of each inequality below and then determine which inequalities have the same solution set as 1 _ 3 ( -5x - 3 ) lt 14
a 1 _ 3 (5x + 3) gt -14 b 2 _ 5 (10x + 20) gt 44
c - 2 _ 5 (10x + 20) lt -44 d - 1 _ 3 (5x + 3) lt 14
e 2 _ 5 (10x - 20) gt -44 f 1 _ 3 (5x + 3) lt -14
HOT Focus on Higher Order Thinking
23 Explain the Error Sven is trying to find the maximum amount of time he can spend practicing the five scales of piano music he is supposed to be working on He has 60 minutes to practice piano and would like to spend at least 35 minutes playing songs instead of practicing scales So Sven sets up the following inequality where t is the number of minutes he spends on each scale and solves it
60 - 5t le 35-5t le -25
t ge 5
Sven has concluded that he should spend 5 minutes or more on each scale Is this correct If not what mistake did he make Then solve for the correct answer
Module 2 79 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
24 Critical Thinking Anika wants to determine the maximum number of tulip bulbs (t) she can purchase if each bulb costs $150 She will also need to purchase separate pots for each bulb at $125 each and a bag of potting soil for $1000 Set up an inequality to determine how many tulip bulbs Anika can purchase without spending more than $2000 and solve it Can Anika buy exactly enough bulbs and pots to spend the full $2000 Explain Can you think of a better inequality to describe the answer
25 Geometry The area of the triangle shown is no more than 10 square inches
a Write an inequality that can be used to find x
b Solve the inequality from part a c What is the maximum height of the triangle
Lesson Performance TaskWhen planning an airplane route the trip planner must be careful to consider the range the aircraft can travel and the availability of airports to stop and refuel
A large commercial jet airplane burns approximately 5 gallons of fuel per mile flown plus about 8500 gallons of fuel per trip to reach cruising altitude With a useable fuel capacity of 50000 gallons (there is additional fuel reserved for emergencies) describe the acceptable distance for which an airline could establish a non-stop flight
For flights originating from Chicago determine which cities could be safely reached by a non-stop flight
City Distance from Chicago (miles)
Bangalore India 8530
Jakarta Indonesia 9810
Johannesburg South Africa 8680
Moscow Russia 4970
Paris France 4130
Perth Australia 10970
Tokyo Japan 6300
copy H
oug
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g Com
pany bull Im
age cred
its copySarych
eva O
lesiaShutterstock
(2x - 3) in
4 in
Module 2 80 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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Name Class Date
Resource Locker
Explore Truth Tables and Compound StatementsA compound statement is formed by combining two or more simple statements A compound statement can be true or false A compound statement involving AND is true when both simple statements are true A compound statement involving OR is true when either one simple statement or both are true
A Complete the truth table
P QP
True or FalseQ
True or FalseP AND Q
True or False
A dog is a mammal Red is a color
A dog is a mammal Red is not a color
A dog is a fish Red is a color
A dog is a fish Red is not a color
B P AND Q is true when
C Complete the truth table
P QP
True or FalseQ
True or FalseP OR Q
True or False
1 is an odd number 2 is an even number
1 is an odd number 2 is an odd number
1 is an even number 2 is an even number
1 is an even number 2 is an odd number
D P OR Q is true when
Reflect
1 Give two simple statements P and Q for which P AND Q is false and P OR Q is true
Module 2 81 Lesson 5
25 Creating and Solving Compound Inequalities
Essential Question How can you solve a compound inequality and graph the solution set
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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Explain 1 Solving Compound Inequalities Involving ANDCombining two or more simple inequalities forms a compound inequality The graph of a compound inequality involving AND is the intersection or the overlapping region of the simple inequality graphs
Compound Inequalities AND
Words Algebra Graph
All real numbers greater than 2AND less than 6
x gt 2 AND x lt 62 lt x lt 6
All real numbers greater than or equal to 2 AND less than or equal to 6
x ge 2 AND x le 62 le x le 6
Example 1 Solve each compound inequality and graph the solutions
A 4 le x + 2 le 8
4 le x + 2 AND x + 2 le 8 Write the compound inequality using AND
4 - 2 le x + 2 - 2 x + 2 - 2 le 8 - 2 Subtract 2 from both sides of each simple inequality
2 le x x le 6 Simplify
Graph 2 le x
Graph x le 6
Graph the intersection by finding where the two graphs overlap
B -5 le 2x + 3 lt 9
-5 - le 2x + 3 - lt 9 - Subtract from each part of the inequality
le 2x lt Simplify
-8 _ le 2x _ lt 6 _ Divide each part of the inequality by
le x lt Simplify
Graph -4 le x
Graph x lt 3
Graph the intersection by finding where the two graphs overlap -1 0 1 2 3 4 5-5-4 -3 -2
0 2 4 6 8 10 12-8-6-4 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 82 Lesson 5
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Reflect
2 Discussion Explain why 2 le x le 6 can be considered the short method for writing the AND compound inequality x ge 2 AND x le 6
YourTurn
Solve each compound inequality and graph the solutions
3 -2 lt x - 3 lt 5
4 -10 lt 3x + 2 le 8
Explain 2 Solving Compound Inequalities Involving ORThe graph of a compound inequality involving OR is the union or the combined region of the simple inequality graphs
Compound Inequalities OR
Words Algebra Graph
All real numbers less than 2OR greater than 6
x lt 2 OR x gt 6
All real numbers less than or equal to 2OR greater than or equal to 6
x le 2 OR x ge 6
-1 0 1 2 3 4 5-5-4 -3 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 83 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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arcourt Publishin
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pany
Example 2 Solve each compound inequality and graph the solutions
A -4 + x gt 1 OR -4 + x lt -3
-4 + x gt 1 OR -4 + x lt -3 Write the compound inequality using OR
-4 + 4 + x gt 1 + 4 -4 + 4 + x lt -3 + 4 Add 4 to both sides of each simple inequality
x gt 5 x lt 1 Simplify
Graph x gt 5
Graph x lt 1
Graph the union by combining the graphs
B 2x le 6 OR 3x gt 12
2x le 6 OR 3x gt 12 Write the compound inequality using OR
2x _ le 6 _ OR 3x _ gt 12 _ Divide the first simple inequality by
x le OR x gt
Graph x le 3
Graph x gt 4
Graph the union by combining the graphs
Reflect
5 Critical Thinking What kind of compound inequality has no solution
Divide the second simple inequality by
Simplify
0 1 2 3 4 5 6-4 -3 -2 -1
-0 1 2 3 4 5 6-4 -3 -2 -1
Module 2 84 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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oug
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Mif
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Har
cour
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lishi
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Com
pan
y
Your Turn
Solve each compound inequality and graph the solutions
6 x - 5 ge -2 OR x -5 le -6
7 4x -1 lt 15 OR 8x ge 48
Explain 3 Creating Compound Inequalities From GraphsGiven a number line graph with a solution set graphed you can create a compound inequality to fit the graph
Example 3 Write the compound inequality shown by each graph
A
The shaded portion of the graph is not between two values so the compound inequality involves OR
On the left the graph shows an arrow pointing left from -1 and a solid circle so use le
The inequality is x le -1
On the right the graph shows an arrow pointing right from 7 and a solid circle so use ge
The inequality is x ge 7
The compound inequality is x le -1 OR x ge 7
B
The graph is shaded between the values and so the compound inequality involves AND
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The compound inequality is
-1 0 1 2 3 4 5-5-4 -3 -2
4 5 6 7 8 9 100 1 2 3
2 3 4 5 6 7 8-2 -1 0 1
10 2 3 4 5 6 7 8 9-1
Module 2 85 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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oug
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arcourt Publishin
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pany
Reflect
8 What is a short method to write the compound inequality x ge 0 AND x lt 6
Your Turn
Write the compound inequality shown by each graph
9
10
Explain 4 Expressing Acceptable Levels with Compound Inequalities
You can express quality-controls levels in real-world problems using compound inequalities
Example 4 Write a compound inequality to represent the indicated quality-control level and graph the solutions
A The recommended pH level for swimming pool water is between 72 and 76 inclusive
Let p be the pH level of swimming pool water
72 is less than or equal to pH level is less than or equal to 76
72 le p le 76
The compound inequality is 72 le p le 76
Graph the solutions
0-10 -8-9 -7-6 -5-4 -3 -2 -1
71 72 73 74 75 76 77 78 79 8070
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 86 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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oug
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Mif
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Har
cour
t Pub
lishi
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Com
pan
y
B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany
bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
copy H
oug
hton
Mif
flin
Har
cour
t Pub
lishi
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Com
pan
y
Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany bull Im
age C
redits copy
Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton
Mif
flin
Har
cour
t Pub
lishi
ng
Com
pan
y bull I
mag
e C
red
its
copy
bik
erid
erlo
nd
onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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pany
The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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pany
Solve each inequality
7 3 (x - 2) gt -3 8 5 + 5 (x + 4) le 20 9 3 + 1 _ 2 (3 - x) lt -7
10 3 (x + 6) - 2 (x + 2) ge 10 11 5 (3 - x) -4 (2 - 3x) gt 2 12 1 _ 2 (4x - 2) - 2 _ 3 (6x + 9) le 4
13 x + 1 gt -5 (7 - 2x) 14 5 _ 3 (6x + 3) le 2x - 7
15 2x le - 2 __ 3 (4x + 4) 16 1 __ 2 (-2x - 10) gt 3 (4 - 6x)
17 -5 - 3x ge 2 (10 + 2x) + 3 18 -3 (9x + 20) ge 15x - 20
19 8 ( 1 _ 4 x - 3) + 24 lt 4 ( x + 5 ) 20 6x - 2 (x + 2) gt 2 - 3 (x + 3)
Module 2 78 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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21 Physics A crane cable can support a maximum load of 15000 kg If a bucket has a mass of 2000 kg and gravel has a mass of 1500 kg for every cubic meter how many cubic meters of gravel (g) can be safely lifted by the crane
22 Find the solution set of each inequality below and then determine which inequalities have the same solution set as 1 _ 3 ( -5x - 3 ) lt 14
a 1 _ 3 (5x + 3) gt -14 b 2 _ 5 (10x + 20) gt 44
c - 2 _ 5 (10x + 20) lt -44 d - 1 _ 3 (5x + 3) lt 14
e 2 _ 5 (10x - 20) gt -44 f 1 _ 3 (5x + 3) lt -14
HOT Focus on Higher Order Thinking
23 Explain the Error Sven is trying to find the maximum amount of time he can spend practicing the five scales of piano music he is supposed to be working on He has 60 minutes to practice piano and would like to spend at least 35 minutes playing songs instead of practicing scales So Sven sets up the following inequality where t is the number of minutes he spends on each scale and solves it
60 - 5t le 35-5t le -25
t ge 5
Sven has concluded that he should spend 5 minutes or more on each scale Is this correct If not what mistake did he make Then solve for the correct answer
Module 2 79 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
24 Critical Thinking Anika wants to determine the maximum number of tulip bulbs (t) she can purchase if each bulb costs $150 She will also need to purchase separate pots for each bulb at $125 each and a bag of potting soil for $1000 Set up an inequality to determine how many tulip bulbs Anika can purchase without spending more than $2000 and solve it Can Anika buy exactly enough bulbs and pots to spend the full $2000 Explain Can you think of a better inequality to describe the answer
25 Geometry The area of the triangle shown is no more than 10 square inches
a Write an inequality that can be used to find x
b Solve the inequality from part a c What is the maximum height of the triangle
Lesson Performance TaskWhen planning an airplane route the trip planner must be careful to consider the range the aircraft can travel and the availability of airports to stop and refuel
A large commercial jet airplane burns approximately 5 gallons of fuel per mile flown plus about 8500 gallons of fuel per trip to reach cruising altitude With a useable fuel capacity of 50000 gallons (there is additional fuel reserved for emergencies) describe the acceptable distance for which an airline could establish a non-stop flight
For flights originating from Chicago determine which cities could be safely reached by a non-stop flight
City Distance from Chicago (miles)
Bangalore India 8530
Jakarta Indonesia 9810
Johannesburg South Africa 8680
Moscow Russia 4970
Paris France 4130
Perth Australia 10970
Tokyo Japan 6300
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany bull Im
age cred
its copySarych
eva O
lesiaShutterstock
(2x - 3) in
4 in
Module 2 80 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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Mif
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lishi
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Name Class Date
Resource Locker
Explore Truth Tables and Compound StatementsA compound statement is formed by combining two or more simple statements A compound statement can be true or false A compound statement involving AND is true when both simple statements are true A compound statement involving OR is true when either one simple statement or both are true
A Complete the truth table
P QP
True or FalseQ
True or FalseP AND Q
True or False
A dog is a mammal Red is a color
A dog is a mammal Red is not a color
A dog is a fish Red is a color
A dog is a fish Red is not a color
B P AND Q is true when
C Complete the truth table
P QP
True or FalseQ
True or FalseP OR Q
True or False
1 is an odd number 2 is an even number
1 is an odd number 2 is an odd number
1 is an even number 2 is an even number
1 is an even number 2 is an odd number
D P OR Q is true when
Reflect
1 Give two simple statements P and Q for which P AND Q is false and P OR Q is true
Module 2 81 Lesson 5
25 Creating and Solving Compound Inequalities
Essential Question How can you solve a compound inequality and graph the solution set
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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Explain 1 Solving Compound Inequalities Involving ANDCombining two or more simple inequalities forms a compound inequality The graph of a compound inequality involving AND is the intersection or the overlapping region of the simple inequality graphs
Compound Inequalities AND
Words Algebra Graph
All real numbers greater than 2AND less than 6
x gt 2 AND x lt 62 lt x lt 6
All real numbers greater than or equal to 2 AND less than or equal to 6
x ge 2 AND x le 62 le x le 6
Example 1 Solve each compound inequality and graph the solutions
A 4 le x + 2 le 8
4 le x + 2 AND x + 2 le 8 Write the compound inequality using AND
4 - 2 le x + 2 - 2 x + 2 - 2 le 8 - 2 Subtract 2 from both sides of each simple inequality
2 le x x le 6 Simplify
Graph 2 le x
Graph x le 6
Graph the intersection by finding where the two graphs overlap
B -5 le 2x + 3 lt 9
-5 - le 2x + 3 - lt 9 - Subtract from each part of the inequality
le 2x lt Simplify
-8 _ le 2x _ lt 6 _ Divide each part of the inequality by
le x lt Simplify
Graph -4 le x
Graph x lt 3
Graph the intersection by finding where the two graphs overlap -1 0 1 2 3 4 5-5-4 -3 -2
0 2 4 6 8 10 12-8-6-4 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 82 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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oug
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pan
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Reflect
2 Discussion Explain why 2 le x le 6 can be considered the short method for writing the AND compound inequality x ge 2 AND x le 6
YourTurn
Solve each compound inequality and graph the solutions
3 -2 lt x - 3 lt 5
4 -10 lt 3x + 2 le 8
Explain 2 Solving Compound Inequalities Involving ORThe graph of a compound inequality involving OR is the union or the combined region of the simple inequality graphs
Compound Inequalities OR
Words Algebra Graph
All real numbers less than 2OR greater than 6
x lt 2 OR x gt 6
All real numbers less than or equal to 2OR greater than or equal to 6
x le 2 OR x ge 6
-1 0 1 2 3 4 5-5-4 -3 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 83 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
arcourt Publishin
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pany
Example 2 Solve each compound inequality and graph the solutions
A -4 + x gt 1 OR -4 + x lt -3
-4 + x gt 1 OR -4 + x lt -3 Write the compound inequality using OR
-4 + 4 + x gt 1 + 4 -4 + 4 + x lt -3 + 4 Add 4 to both sides of each simple inequality
x gt 5 x lt 1 Simplify
Graph x gt 5
Graph x lt 1
Graph the union by combining the graphs
B 2x le 6 OR 3x gt 12
2x le 6 OR 3x gt 12 Write the compound inequality using OR
2x _ le 6 _ OR 3x _ gt 12 _ Divide the first simple inequality by
x le OR x gt
Graph x le 3
Graph x gt 4
Graph the union by combining the graphs
Reflect
5 Critical Thinking What kind of compound inequality has no solution
Divide the second simple inequality by
Simplify
0 1 2 3 4 5 6-4 -3 -2 -1
-0 1 2 3 4 5 6-4 -3 -2 -1
Module 2 84 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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oug
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cour
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Com
pan
y
Your Turn
Solve each compound inequality and graph the solutions
6 x - 5 ge -2 OR x -5 le -6
7 4x -1 lt 15 OR 8x ge 48
Explain 3 Creating Compound Inequalities From GraphsGiven a number line graph with a solution set graphed you can create a compound inequality to fit the graph
Example 3 Write the compound inequality shown by each graph
A
The shaded portion of the graph is not between two values so the compound inequality involves OR
On the left the graph shows an arrow pointing left from -1 and a solid circle so use le
The inequality is x le -1
On the right the graph shows an arrow pointing right from 7 and a solid circle so use ge
The inequality is x ge 7
The compound inequality is x le -1 OR x ge 7
B
The graph is shaded between the values and so the compound inequality involves AND
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The compound inequality is
-1 0 1 2 3 4 5-5-4 -3 -2
4 5 6 7 8 9 100 1 2 3
2 3 4 5 6 7 8-2 -1 0 1
10 2 3 4 5 6 7 8 9-1
Module 2 85 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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oug
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Reflect
8 What is a short method to write the compound inequality x ge 0 AND x lt 6
Your Turn
Write the compound inequality shown by each graph
9
10
Explain 4 Expressing Acceptable Levels with Compound Inequalities
You can express quality-controls levels in real-world problems using compound inequalities
Example 4 Write a compound inequality to represent the indicated quality-control level and graph the solutions
A The recommended pH level for swimming pool water is between 72 and 76 inclusive
Let p be the pH level of swimming pool water
72 is less than or equal to pH level is less than or equal to 76
72 le p le 76
The compound inequality is 72 le p le 76
Graph the solutions
0-10 -8-9 -7-6 -5-4 -3 -2 -1
71 72 73 74 75 76 77 78 79 8070
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 86 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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oug
hton
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cour
t Pub
lishi
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pan
y
B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
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bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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oug
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Har
cour
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Com
pan
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Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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arcourt Publishin
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pany bull Im
age C
redits copy
Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
hton
Mif
flin
Har
cour
t Pub
lishi
ng
Com
pan
y bull I
mag
e C
red
its
copy
bik
erid
erlo
nd
onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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arcourt Publishin
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pany
The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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Mif
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Har
cour
t Pub
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Com
pan
y
21 Physics A crane cable can support a maximum load of 15000 kg If a bucket has a mass of 2000 kg and gravel has a mass of 1500 kg for every cubic meter how many cubic meters of gravel (g) can be safely lifted by the crane
22 Find the solution set of each inequality below and then determine which inequalities have the same solution set as 1 _ 3 ( -5x - 3 ) lt 14
a 1 _ 3 (5x + 3) gt -14 b 2 _ 5 (10x + 20) gt 44
c - 2 _ 5 (10x + 20) lt -44 d - 1 _ 3 (5x + 3) lt 14
e 2 _ 5 (10x - 20) gt -44 f 1 _ 3 (5x + 3) lt -14
HOT Focus on Higher Order Thinking
23 Explain the Error Sven is trying to find the maximum amount of time he can spend practicing the five scales of piano music he is supposed to be working on He has 60 minutes to practice piano and would like to spend at least 35 minutes playing songs instead of practicing scales So Sven sets up the following inequality where t is the number of minutes he spends on each scale and solves it
60 - 5t le 35-5t le -25
t ge 5
Sven has concluded that he should spend 5 minutes or more on each scale Is this correct If not what mistake did he make Then solve for the correct answer
Module 2 79 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
24 Critical Thinking Anika wants to determine the maximum number of tulip bulbs (t) she can purchase if each bulb costs $150 She will also need to purchase separate pots for each bulb at $125 each and a bag of potting soil for $1000 Set up an inequality to determine how many tulip bulbs Anika can purchase without spending more than $2000 and solve it Can Anika buy exactly enough bulbs and pots to spend the full $2000 Explain Can you think of a better inequality to describe the answer
25 Geometry The area of the triangle shown is no more than 10 square inches
a Write an inequality that can be used to find x
b Solve the inequality from part a c What is the maximum height of the triangle
Lesson Performance TaskWhen planning an airplane route the trip planner must be careful to consider the range the aircraft can travel and the availability of airports to stop and refuel
A large commercial jet airplane burns approximately 5 gallons of fuel per mile flown plus about 8500 gallons of fuel per trip to reach cruising altitude With a useable fuel capacity of 50000 gallons (there is additional fuel reserved for emergencies) describe the acceptable distance for which an airline could establish a non-stop flight
For flights originating from Chicago determine which cities could be safely reached by a non-stop flight
City Distance from Chicago (miles)
Bangalore India 8530
Jakarta Indonesia 9810
Johannesburg South Africa 8680
Moscow Russia 4970
Paris France 4130
Perth Australia 10970
Tokyo Japan 6300
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany bull Im
age cred
its copySarych
eva O
lesiaShutterstock
(2x - 3) in
4 in
Module 2 80 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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Mif
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Har
cour
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pan
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Name Class Date
Resource Locker
Explore Truth Tables and Compound StatementsA compound statement is formed by combining two or more simple statements A compound statement can be true or false A compound statement involving AND is true when both simple statements are true A compound statement involving OR is true when either one simple statement or both are true
A Complete the truth table
P QP
True or FalseQ
True or FalseP AND Q
True or False
A dog is a mammal Red is a color
A dog is a mammal Red is not a color
A dog is a fish Red is a color
A dog is a fish Red is not a color
B P AND Q is true when
C Complete the truth table
P QP
True or FalseQ
True or FalseP OR Q
True or False
1 is an odd number 2 is an even number
1 is an odd number 2 is an odd number
1 is an even number 2 is an even number
1 is an even number 2 is an odd number
D P OR Q is true when
Reflect
1 Give two simple statements P and Q for which P AND Q is false and P OR Q is true
Module 2 81 Lesson 5
25 Creating and Solving Compound Inequalities
Essential Question How can you solve a compound inequality and graph the solution set
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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pany
Explain 1 Solving Compound Inequalities Involving ANDCombining two or more simple inequalities forms a compound inequality The graph of a compound inequality involving AND is the intersection or the overlapping region of the simple inequality graphs
Compound Inequalities AND
Words Algebra Graph
All real numbers greater than 2AND less than 6
x gt 2 AND x lt 62 lt x lt 6
All real numbers greater than or equal to 2 AND less than or equal to 6
x ge 2 AND x le 62 le x le 6
Example 1 Solve each compound inequality and graph the solutions
A 4 le x + 2 le 8
4 le x + 2 AND x + 2 le 8 Write the compound inequality using AND
4 - 2 le x + 2 - 2 x + 2 - 2 le 8 - 2 Subtract 2 from both sides of each simple inequality
2 le x x le 6 Simplify
Graph 2 le x
Graph x le 6
Graph the intersection by finding where the two graphs overlap
B -5 le 2x + 3 lt 9
-5 - le 2x + 3 - lt 9 - Subtract from each part of the inequality
le 2x lt Simplify
-8 _ le 2x _ lt 6 _ Divide each part of the inequality by
le x lt Simplify
Graph -4 le x
Graph x lt 3
Graph the intersection by finding where the two graphs overlap -1 0 1 2 3 4 5-5-4 -3 -2
0 2 4 6 8 10 12-8-6-4 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 82 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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oug
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cour
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lishi
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Com
pan
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Reflect
2 Discussion Explain why 2 le x le 6 can be considered the short method for writing the AND compound inequality x ge 2 AND x le 6
YourTurn
Solve each compound inequality and graph the solutions
3 -2 lt x - 3 lt 5
4 -10 lt 3x + 2 le 8
Explain 2 Solving Compound Inequalities Involving ORThe graph of a compound inequality involving OR is the union or the combined region of the simple inequality graphs
Compound Inequalities OR
Words Algebra Graph
All real numbers less than 2OR greater than 6
x lt 2 OR x gt 6
All real numbers less than or equal to 2OR greater than or equal to 6
x le 2 OR x ge 6
-1 0 1 2 3 4 5-5-4 -3 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 83 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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arcourt Publishin
g Com
pany
Example 2 Solve each compound inequality and graph the solutions
A -4 + x gt 1 OR -4 + x lt -3
-4 + x gt 1 OR -4 + x lt -3 Write the compound inequality using OR
-4 + 4 + x gt 1 + 4 -4 + 4 + x lt -3 + 4 Add 4 to both sides of each simple inequality
x gt 5 x lt 1 Simplify
Graph x gt 5
Graph x lt 1
Graph the union by combining the graphs
B 2x le 6 OR 3x gt 12
2x le 6 OR 3x gt 12 Write the compound inequality using OR
2x _ le 6 _ OR 3x _ gt 12 _ Divide the first simple inequality by
x le OR x gt
Graph x le 3
Graph x gt 4
Graph the union by combining the graphs
Reflect
5 Critical Thinking What kind of compound inequality has no solution
Divide the second simple inequality by
Simplify
0 1 2 3 4 5 6-4 -3 -2 -1
-0 1 2 3 4 5 6-4 -3 -2 -1
Module 2 84 Lesson 5
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oug
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t Pub
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pan
y
Your Turn
Solve each compound inequality and graph the solutions
6 x - 5 ge -2 OR x -5 le -6
7 4x -1 lt 15 OR 8x ge 48
Explain 3 Creating Compound Inequalities From GraphsGiven a number line graph with a solution set graphed you can create a compound inequality to fit the graph
Example 3 Write the compound inequality shown by each graph
A
The shaded portion of the graph is not between two values so the compound inequality involves OR
On the left the graph shows an arrow pointing left from -1 and a solid circle so use le
The inequality is x le -1
On the right the graph shows an arrow pointing right from 7 and a solid circle so use ge
The inequality is x ge 7
The compound inequality is x le -1 OR x ge 7
B
The graph is shaded between the values and so the compound inequality involves AND
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The compound inequality is
-1 0 1 2 3 4 5-5-4 -3 -2
4 5 6 7 8 9 100 1 2 3
2 3 4 5 6 7 8-2 -1 0 1
10 2 3 4 5 6 7 8 9-1
Module 2 85 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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oug
hton Mifflin H
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pany
Reflect
8 What is a short method to write the compound inequality x ge 0 AND x lt 6
Your Turn
Write the compound inequality shown by each graph
9
10
Explain 4 Expressing Acceptable Levels with Compound Inequalities
You can express quality-controls levels in real-world problems using compound inequalities
Example 4 Write a compound inequality to represent the indicated quality-control level and graph the solutions
A The recommended pH level for swimming pool water is between 72 and 76 inclusive
Let p be the pH level of swimming pool water
72 is less than or equal to pH level is less than or equal to 76
72 le p le 76
The compound inequality is 72 le p le 76
Graph the solutions
0-10 -8-9 -7-6 -5-4 -3 -2 -1
71 72 73 74 75 76 77 78 79 8070
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 86 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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oug
hton
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t Pub
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pan
y
B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
arcourt Publishin
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pany
bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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oug
hton
Mif
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Har
cour
t Pub
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ng
Com
pan
y
Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
arcourt Publishin
g Com
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Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
hton
Mif
flin
Har
cour
t Pub
lishi
ng
Com
pan
y bull I
mag
e C
red
its
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bik
erid
erlo
nd
onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
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pany
The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
24 Critical Thinking Anika wants to determine the maximum number of tulip bulbs (t) she can purchase if each bulb costs $150 She will also need to purchase separate pots for each bulb at $125 each and a bag of potting soil for $1000 Set up an inequality to determine how many tulip bulbs Anika can purchase without spending more than $2000 and solve it Can Anika buy exactly enough bulbs and pots to spend the full $2000 Explain Can you think of a better inequality to describe the answer
25 Geometry The area of the triangle shown is no more than 10 square inches
a Write an inequality that can be used to find x
b Solve the inequality from part a c What is the maximum height of the triangle
Lesson Performance TaskWhen planning an airplane route the trip planner must be careful to consider the range the aircraft can travel and the availability of airports to stop and refuel
A large commercial jet airplane burns approximately 5 gallons of fuel per mile flown plus about 8500 gallons of fuel per trip to reach cruising altitude With a useable fuel capacity of 50000 gallons (there is additional fuel reserved for emergencies) describe the acceptable distance for which an airline could establish a non-stop flight
For flights originating from Chicago determine which cities could be safely reached by a non-stop flight
City Distance from Chicago (miles)
Bangalore India 8530
Jakarta Indonesia 9810
Johannesburg South Africa 8680
Moscow Russia 4970
Paris France 4130
Perth Australia 10970
Tokyo Japan 6300
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany bull Im
age cred
its copySarych
eva O
lesiaShutterstock
(2x - 3) in
4 in
Module 2 80 Lesson 4
DO NOT EDIT--Changes must be made through ldquoFile infordquo CorrectionKey=NL-BCA-B
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oug
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Name Class Date
Resource Locker
Explore Truth Tables and Compound StatementsA compound statement is formed by combining two or more simple statements A compound statement can be true or false A compound statement involving AND is true when both simple statements are true A compound statement involving OR is true when either one simple statement or both are true
A Complete the truth table
P QP
True or FalseQ
True or FalseP AND Q
True or False
A dog is a mammal Red is a color
A dog is a mammal Red is not a color
A dog is a fish Red is a color
A dog is a fish Red is not a color
B P AND Q is true when
C Complete the truth table
P QP
True or FalseQ
True or FalseP OR Q
True or False
1 is an odd number 2 is an even number
1 is an odd number 2 is an odd number
1 is an even number 2 is an even number
1 is an even number 2 is an odd number
D P OR Q is true when
Reflect
1 Give two simple statements P and Q for which P AND Q is false and P OR Q is true
Module 2 81 Lesson 5
25 Creating and Solving Compound Inequalities
Essential Question How can you solve a compound inequality and graph the solution set
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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Explain 1 Solving Compound Inequalities Involving ANDCombining two or more simple inequalities forms a compound inequality The graph of a compound inequality involving AND is the intersection or the overlapping region of the simple inequality graphs
Compound Inequalities AND
Words Algebra Graph
All real numbers greater than 2AND less than 6
x gt 2 AND x lt 62 lt x lt 6
All real numbers greater than or equal to 2 AND less than or equal to 6
x ge 2 AND x le 62 le x le 6
Example 1 Solve each compound inequality and graph the solutions
A 4 le x + 2 le 8
4 le x + 2 AND x + 2 le 8 Write the compound inequality using AND
4 - 2 le x + 2 - 2 x + 2 - 2 le 8 - 2 Subtract 2 from both sides of each simple inequality
2 le x x le 6 Simplify
Graph 2 le x
Graph x le 6
Graph the intersection by finding where the two graphs overlap
B -5 le 2x + 3 lt 9
-5 - le 2x + 3 - lt 9 - Subtract from each part of the inequality
le 2x lt Simplify
-8 _ le 2x _ lt 6 _ Divide each part of the inequality by
le x lt Simplify
Graph -4 le x
Graph x lt 3
Graph the intersection by finding where the two graphs overlap -1 0 1 2 3 4 5-5-4 -3 -2
0 2 4 6 8 10 12-8-6-4 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 82 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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oug
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pan
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Reflect
2 Discussion Explain why 2 le x le 6 can be considered the short method for writing the AND compound inequality x ge 2 AND x le 6
YourTurn
Solve each compound inequality and graph the solutions
3 -2 lt x - 3 lt 5
4 -10 lt 3x + 2 le 8
Explain 2 Solving Compound Inequalities Involving ORThe graph of a compound inequality involving OR is the union or the combined region of the simple inequality graphs
Compound Inequalities OR
Words Algebra Graph
All real numbers less than 2OR greater than 6
x lt 2 OR x gt 6
All real numbers less than or equal to 2OR greater than or equal to 6
x le 2 OR x ge 6
-1 0 1 2 3 4 5-5-4 -3 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 83 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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arcourt Publishin
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Example 2 Solve each compound inequality and graph the solutions
A -4 + x gt 1 OR -4 + x lt -3
-4 + x gt 1 OR -4 + x lt -3 Write the compound inequality using OR
-4 + 4 + x gt 1 + 4 -4 + 4 + x lt -3 + 4 Add 4 to both sides of each simple inequality
x gt 5 x lt 1 Simplify
Graph x gt 5
Graph x lt 1
Graph the union by combining the graphs
B 2x le 6 OR 3x gt 12
2x le 6 OR 3x gt 12 Write the compound inequality using OR
2x _ le 6 _ OR 3x _ gt 12 _ Divide the first simple inequality by
x le OR x gt
Graph x le 3
Graph x gt 4
Graph the union by combining the graphs
Reflect
5 Critical Thinking What kind of compound inequality has no solution
Divide the second simple inequality by
Simplify
0 1 2 3 4 5 6-4 -3 -2 -1
-0 1 2 3 4 5 6-4 -3 -2 -1
Module 2 84 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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oug
hton
Mif
flin
Har
cour
t Pub
lishi
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Com
pan
y
Your Turn
Solve each compound inequality and graph the solutions
6 x - 5 ge -2 OR x -5 le -6
7 4x -1 lt 15 OR 8x ge 48
Explain 3 Creating Compound Inequalities From GraphsGiven a number line graph with a solution set graphed you can create a compound inequality to fit the graph
Example 3 Write the compound inequality shown by each graph
A
The shaded portion of the graph is not between two values so the compound inequality involves OR
On the left the graph shows an arrow pointing left from -1 and a solid circle so use le
The inequality is x le -1
On the right the graph shows an arrow pointing right from 7 and a solid circle so use ge
The inequality is x ge 7
The compound inequality is x le -1 OR x ge 7
B
The graph is shaded between the values and so the compound inequality involves AND
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The compound inequality is
-1 0 1 2 3 4 5-5-4 -3 -2
4 5 6 7 8 9 100 1 2 3
2 3 4 5 6 7 8-2 -1 0 1
10 2 3 4 5 6 7 8 9-1
Module 2 85 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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oug
hton Mifflin H
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Reflect
8 What is a short method to write the compound inequality x ge 0 AND x lt 6
Your Turn
Write the compound inequality shown by each graph
9
10
Explain 4 Expressing Acceptable Levels with Compound Inequalities
You can express quality-controls levels in real-world problems using compound inequalities
Example 4 Write a compound inequality to represent the indicated quality-control level and graph the solutions
A The recommended pH level for swimming pool water is between 72 and 76 inclusive
Let p be the pH level of swimming pool water
72 is less than or equal to pH level is less than or equal to 76
72 le p le 76
The compound inequality is 72 le p le 76
Graph the solutions
0-10 -8-9 -7-6 -5-4 -3 -2 -1
71 72 73 74 75 76 77 78 79 8070
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 86 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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oug
hton
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flin
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cour
t Pub
lishi
ng
Com
pan
y
B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany
bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
copy H
oug
hton
Mif
flin
Har
cour
t Pub
lishi
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Com
pan
y
Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany bull Im
age C
redits copy
Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton
Mif
flin
Har
cour
t Pub
lishi
ng
Com
pan
y bull I
mag
e C
red
its
copy
bik
erid
erlo
nd
onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
arcourt Publishin
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pany
The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton
Mif
flin
Har
cour
t Pub
lishi
ng
Com
pan
y
Name Class Date
Resource Locker
Explore Truth Tables and Compound StatementsA compound statement is formed by combining two or more simple statements A compound statement can be true or false A compound statement involving AND is true when both simple statements are true A compound statement involving OR is true when either one simple statement or both are true
A Complete the truth table
P QP
True or FalseQ
True or FalseP AND Q
True or False
A dog is a mammal Red is a color
A dog is a mammal Red is not a color
A dog is a fish Red is a color
A dog is a fish Red is not a color
B P AND Q is true when
C Complete the truth table
P QP
True or FalseQ
True or FalseP OR Q
True or False
1 is an odd number 2 is an even number
1 is an odd number 2 is an odd number
1 is an even number 2 is an even number
1 is an even number 2 is an odd number
D P OR Q is true when
Reflect
1 Give two simple statements P and Q for which P AND Q is false and P OR Q is true
Module 2 81 Lesson 5
25 Creating and Solving Compound Inequalities
Essential Question How can you solve a compound inequality and graph the solution set
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany
Explain 1 Solving Compound Inequalities Involving ANDCombining two or more simple inequalities forms a compound inequality The graph of a compound inequality involving AND is the intersection or the overlapping region of the simple inequality graphs
Compound Inequalities AND
Words Algebra Graph
All real numbers greater than 2AND less than 6
x gt 2 AND x lt 62 lt x lt 6
All real numbers greater than or equal to 2 AND less than or equal to 6
x ge 2 AND x le 62 le x le 6
Example 1 Solve each compound inequality and graph the solutions
A 4 le x + 2 le 8
4 le x + 2 AND x + 2 le 8 Write the compound inequality using AND
4 - 2 le x + 2 - 2 x + 2 - 2 le 8 - 2 Subtract 2 from both sides of each simple inequality
2 le x x le 6 Simplify
Graph 2 le x
Graph x le 6
Graph the intersection by finding where the two graphs overlap
B -5 le 2x + 3 lt 9
-5 - le 2x + 3 - lt 9 - Subtract from each part of the inequality
le 2x lt Simplify
-8 _ le 2x _ lt 6 _ Divide each part of the inequality by
le x lt Simplify
Graph -4 le x
Graph x lt 3
Graph the intersection by finding where the two graphs overlap -1 0 1 2 3 4 5-5-4 -3 -2
0 2 4 6 8 10 12-8-6-4 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 82 Lesson 5
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oug
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pan
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Reflect
2 Discussion Explain why 2 le x le 6 can be considered the short method for writing the AND compound inequality x ge 2 AND x le 6
YourTurn
Solve each compound inequality and graph the solutions
3 -2 lt x - 3 lt 5
4 -10 lt 3x + 2 le 8
Explain 2 Solving Compound Inequalities Involving ORThe graph of a compound inequality involving OR is the union or the combined region of the simple inequality graphs
Compound Inequalities OR
Words Algebra Graph
All real numbers less than 2OR greater than 6
x lt 2 OR x gt 6
All real numbers less than or equal to 2OR greater than or equal to 6
x le 2 OR x ge 6
-1 0 1 2 3 4 5-5-4 -3 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 83 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
arcourt Publishin
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pany
Example 2 Solve each compound inequality and graph the solutions
A -4 + x gt 1 OR -4 + x lt -3
-4 + x gt 1 OR -4 + x lt -3 Write the compound inequality using OR
-4 + 4 + x gt 1 + 4 -4 + 4 + x lt -3 + 4 Add 4 to both sides of each simple inequality
x gt 5 x lt 1 Simplify
Graph x gt 5
Graph x lt 1
Graph the union by combining the graphs
B 2x le 6 OR 3x gt 12
2x le 6 OR 3x gt 12 Write the compound inequality using OR
2x _ le 6 _ OR 3x _ gt 12 _ Divide the first simple inequality by
x le OR x gt
Graph x le 3
Graph x gt 4
Graph the union by combining the graphs
Reflect
5 Critical Thinking What kind of compound inequality has no solution
Divide the second simple inequality by
Simplify
0 1 2 3 4 5 6-4 -3 -2 -1
-0 1 2 3 4 5 6-4 -3 -2 -1
Module 2 84 Lesson 5
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oug
hton
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Your Turn
Solve each compound inequality and graph the solutions
6 x - 5 ge -2 OR x -5 le -6
7 4x -1 lt 15 OR 8x ge 48
Explain 3 Creating Compound Inequalities From GraphsGiven a number line graph with a solution set graphed you can create a compound inequality to fit the graph
Example 3 Write the compound inequality shown by each graph
A
The shaded portion of the graph is not between two values so the compound inequality involves OR
On the left the graph shows an arrow pointing left from -1 and a solid circle so use le
The inequality is x le -1
On the right the graph shows an arrow pointing right from 7 and a solid circle so use ge
The inequality is x ge 7
The compound inequality is x le -1 OR x ge 7
B
The graph is shaded between the values and so the compound inequality involves AND
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The compound inequality is
-1 0 1 2 3 4 5-5-4 -3 -2
4 5 6 7 8 9 100 1 2 3
2 3 4 5 6 7 8-2 -1 0 1
10 2 3 4 5 6 7 8 9-1
Module 2 85 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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oug
hton Mifflin H
arcourt Publishin
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Reflect
8 What is a short method to write the compound inequality x ge 0 AND x lt 6
Your Turn
Write the compound inequality shown by each graph
9
10
Explain 4 Expressing Acceptable Levels with Compound Inequalities
You can express quality-controls levels in real-world problems using compound inequalities
Example 4 Write a compound inequality to represent the indicated quality-control level and graph the solutions
A The recommended pH level for swimming pool water is between 72 and 76 inclusive
Let p be the pH level of swimming pool water
72 is less than or equal to pH level is less than or equal to 76
72 le p le 76
The compound inequality is 72 le p le 76
Graph the solutions
0-10 -8-9 -7-6 -5-4 -3 -2 -1
71 72 73 74 75 76 77 78 79 8070
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 86 Lesson 5
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oug
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B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
arcourt Publishin
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pany
bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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oug
hton
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Har
cour
t Pub
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pan
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Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
arcourt Publishin
g Com
pany bull Im
age C
redits copy
Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton
Mif
flin
Har
cour
t Pub
lishi
ng
Com
pan
y bull I
mag
e C
red
its
copy
bik
erid
erlo
nd
onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
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arcourt Publishin
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Explain 1 Solving Compound Inequalities Involving ANDCombining two or more simple inequalities forms a compound inequality The graph of a compound inequality involving AND is the intersection or the overlapping region of the simple inequality graphs
Compound Inequalities AND
Words Algebra Graph
All real numbers greater than 2AND less than 6
x gt 2 AND x lt 62 lt x lt 6
All real numbers greater than or equal to 2 AND less than or equal to 6
x ge 2 AND x le 62 le x le 6
Example 1 Solve each compound inequality and graph the solutions
A 4 le x + 2 le 8
4 le x + 2 AND x + 2 le 8 Write the compound inequality using AND
4 - 2 le x + 2 - 2 x + 2 - 2 le 8 - 2 Subtract 2 from both sides of each simple inequality
2 le x x le 6 Simplify
Graph 2 le x
Graph x le 6
Graph the intersection by finding where the two graphs overlap
B -5 le 2x + 3 lt 9
-5 - le 2x + 3 - lt 9 - Subtract from each part of the inequality
le 2x lt Simplify
-8 _ le 2x _ lt 6 _ Divide each part of the inequality by
le x lt Simplify
Graph -4 le x
Graph x lt 3
Graph the intersection by finding where the two graphs overlap -1 0 1 2 3 4 5-5-4 -3 -2
0 2 4 6 8 10 12-8-6-4 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 82 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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oug
hton
Mif
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Har
cour
t Pub
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pan
y
Reflect
2 Discussion Explain why 2 le x le 6 can be considered the short method for writing the AND compound inequality x ge 2 AND x le 6
YourTurn
Solve each compound inequality and graph the solutions
3 -2 lt x - 3 lt 5
4 -10 lt 3x + 2 le 8
Explain 2 Solving Compound Inequalities Involving ORThe graph of a compound inequality involving OR is the union or the combined region of the simple inequality graphs
Compound Inequalities OR
Words Algebra Graph
All real numbers less than 2OR greater than 6
x lt 2 OR x gt 6
All real numbers less than or equal to 2OR greater than or equal to 6
x le 2 OR x ge 6
-1 0 1 2 3 4 5-5-4 -3 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 83 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
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oug
hton Mifflin H
arcourt Publishin
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Example 2 Solve each compound inequality and graph the solutions
A -4 + x gt 1 OR -4 + x lt -3
-4 + x gt 1 OR -4 + x lt -3 Write the compound inequality using OR
-4 + 4 + x gt 1 + 4 -4 + 4 + x lt -3 + 4 Add 4 to both sides of each simple inequality
x gt 5 x lt 1 Simplify
Graph x gt 5
Graph x lt 1
Graph the union by combining the graphs
B 2x le 6 OR 3x gt 12
2x le 6 OR 3x gt 12 Write the compound inequality using OR
2x _ le 6 _ OR 3x _ gt 12 _ Divide the first simple inequality by
x le OR x gt
Graph x le 3
Graph x gt 4
Graph the union by combining the graphs
Reflect
5 Critical Thinking What kind of compound inequality has no solution
Divide the second simple inequality by
Simplify
0 1 2 3 4 5 6-4 -3 -2 -1
-0 1 2 3 4 5 6-4 -3 -2 -1
Module 2 84 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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oug
hton
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cour
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pan
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Your Turn
Solve each compound inequality and graph the solutions
6 x - 5 ge -2 OR x -5 le -6
7 4x -1 lt 15 OR 8x ge 48
Explain 3 Creating Compound Inequalities From GraphsGiven a number line graph with a solution set graphed you can create a compound inequality to fit the graph
Example 3 Write the compound inequality shown by each graph
A
The shaded portion of the graph is not between two values so the compound inequality involves OR
On the left the graph shows an arrow pointing left from -1 and a solid circle so use le
The inequality is x le -1
On the right the graph shows an arrow pointing right from 7 and a solid circle so use ge
The inequality is x ge 7
The compound inequality is x le -1 OR x ge 7
B
The graph is shaded between the values and so the compound inequality involves AND
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The compound inequality is
-1 0 1 2 3 4 5-5-4 -3 -2
4 5 6 7 8 9 100 1 2 3
2 3 4 5 6 7 8-2 -1 0 1
10 2 3 4 5 6 7 8 9-1
Module 2 85 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
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pany
Reflect
8 What is a short method to write the compound inequality x ge 0 AND x lt 6
Your Turn
Write the compound inequality shown by each graph
9
10
Explain 4 Expressing Acceptable Levels with Compound Inequalities
You can express quality-controls levels in real-world problems using compound inequalities
Example 4 Write a compound inequality to represent the indicated quality-control level and graph the solutions
A The recommended pH level for swimming pool water is between 72 and 76 inclusive
Let p be the pH level of swimming pool water
72 is less than or equal to pH level is less than or equal to 76
72 le p le 76
The compound inequality is 72 le p le 76
Graph the solutions
0-10 -8-9 -7-6 -5-4 -3 -2 -1
71 72 73 74 75 76 77 78 79 8070
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 86 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
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oug
hton
Mif
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Har
cour
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pan
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B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany
bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
copy H
oug
hton
Mif
flin
Har
cour
t Pub
lishi
ng
Com
pan
y
Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany bull Im
age C
redits copy
Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton
Mif
flin
Har
cour
t Pub
lishi
ng
Com
pan
y bull I
mag
e C
red
its
copy
bik
erid
erlo
nd
onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany
The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton
Mif
flin
Har
cour
t Pub
lishi
ng
Com
pan
y
Reflect
2 Discussion Explain why 2 le x le 6 can be considered the short method for writing the AND compound inequality x ge 2 AND x le 6
YourTurn
Solve each compound inequality and graph the solutions
3 -2 lt x - 3 lt 5
4 -10 lt 3x + 2 le 8
Explain 2 Solving Compound Inequalities Involving ORThe graph of a compound inequality involving OR is the union or the combined region of the simple inequality graphs
Compound Inequalities OR
Words Algebra Graph
All real numbers less than 2OR greater than 6
x lt 2 OR x gt 6
All real numbers less than or equal to 2OR greater than or equal to 6
x le 2 OR x ge 6
-1 0 1 2 3 4 5-5-4 -3 -2
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
1 2 3 4 5 6 7 8 9 100
Module 2 83 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany
Example 2 Solve each compound inequality and graph the solutions
A -4 + x gt 1 OR -4 + x lt -3
-4 + x gt 1 OR -4 + x lt -3 Write the compound inequality using OR
-4 + 4 + x gt 1 + 4 -4 + 4 + x lt -3 + 4 Add 4 to both sides of each simple inequality
x gt 5 x lt 1 Simplify
Graph x gt 5
Graph x lt 1
Graph the union by combining the graphs
B 2x le 6 OR 3x gt 12
2x le 6 OR 3x gt 12 Write the compound inequality using OR
2x _ le 6 _ OR 3x _ gt 12 _ Divide the first simple inequality by
x le OR x gt
Graph x le 3
Graph x gt 4
Graph the union by combining the graphs
Reflect
5 Critical Thinking What kind of compound inequality has no solution
Divide the second simple inequality by
Simplify
0 1 2 3 4 5 6-4 -3 -2 -1
-0 1 2 3 4 5 6-4 -3 -2 -1
Module 2 84 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
copy H
oug
hton
Mif
flin
Har
cour
t Pub
lishi
ng
Com
pan
y
Your Turn
Solve each compound inequality and graph the solutions
6 x - 5 ge -2 OR x -5 le -6
7 4x -1 lt 15 OR 8x ge 48
Explain 3 Creating Compound Inequalities From GraphsGiven a number line graph with a solution set graphed you can create a compound inequality to fit the graph
Example 3 Write the compound inequality shown by each graph
A
The shaded portion of the graph is not between two values so the compound inequality involves OR
On the left the graph shows an arrow pointing left from -1 and a solid circle so use le
The inequality is x le -1
On the right the graph shows an arrow pointing right from 7 and a solid circle so use ge
The inequality is x ge 7
The compound inequality is x le -1 OR x ge 7
B
The graph is shaded between the values and so the compound inequality involves AND
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The compound inequality is
-1 0 1 2 3 4 5-5-4 -3 -2
4 5 6 7 8 9 100 1 2 3
2 3 4 5 6 7 8-2 -1 0 1
10 2 3 4 5 6 7 8 9-1
Module 2 85 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany
Reflect
8 What is a short method to write the compound inequality x ge 0 AND x lt 6
Your Turn
Write the compound inequality shown by each graph
9
10
Explain 4 Expressing Acceptable Levels with Compound Inequalities
You can express quality-controls levels in real-world problems using compound inequalities
Example 4 Write a compound inequality to represent the indicated quality-control level and graph the solutions
A The recommended pH level for swimming pool water is between 72 and 76 inclusive
Let p be the pH level of swimming pool water
72 is less than or equal to pH level is less than or equal to 76
72 le p le 76
The compound inequality is 72 le p le 76
Graph the solutions
0-10 -8-9 -7-6 -5-4 -3 -2 -1
71 72 73 74 75 76 77 78 79 8070
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 86 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
copy H
oug
hton
Mif
flin
Har
cour
t Pub
lishi
ng
Com
pan
y
B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany
bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
copy H
oug
hton
Mif
flin
Har
cour
t Pub
lishi
ng
Com
pan
y
Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany bull Im
age C
redits copy
Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton
Mif
flin
Har
cour
t Pub
lishi
ng
Com
pan
y bull I
mag
e C
red
its
copy
bik
erid
erlo
nd
onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany
The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany
Example 2 Solve each compound inequality and graph the solutions
A -4 + x gt 1 OR -4 + x lt -3
-4 + x gt 1 OR -4 + x lt -3 Write the compound inequality using OR
-4 + 4 + x gt 1 + 4 -4 + 4 + x lt -3 + 4 Add 4 to both sides of each simple inequality
x gt 5 x lt 1 Simplify
Graph x gt 5
Graph x lt 1
Graph the union by combining the graphs
B 2x le 6 OR 3x gt 12
2x le 6 OR 3x gt 12 Write the compound inequality using OR
2x _ le 6 _ OR 3x _ gt 12 _ Divide the first simple inequality by
x le OR x gt
Graph x le 3
Graph x gt 4
Graph the union by combining the graphs
Reflect
5 Critical Thinking What kind of compound inequality has no solution
Divide the second simple inequality by
Simplify
0 1 2 3 4 5 6-4 -3 -2 -1
-0 1 2 3 4 5 6-4 -3 -2 -1
Module 2 84 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
copy H
oug
hton
Mif
flin
Har
cour
t Pub
lishi
ng
Com
pan
y
Your Turn
Solve each compound inequality and graph the solutions
6 x - 5 ge -2 OR x -5 le -6
7 4x -1 lt 15 OR 8x ge 48
Explain 3 Creating Compound Inequalities From GraphsGiven a number line graph with a solution set graphed you can create a compound inequality to fit the graph
Example 3 Write the compound inequality shown by each graph
A
The shaded portion of the graph is not between two values so the compound inequality involves OR
On the left the graph shows an arrow pointing left from -1 and a solid circle so use le
The inequality is x le -1
On the right the graph shows an arrow pointing right from 7 and a solid circle so use ge
The inequality is x ge 7
The compound inequality is x le -1 OR x ge 7
B
The graph is shaded between the values and so the compound inequality involves AND
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The compound inequality is
-1 0 1 2 3 4 5-5-4 -3 -2
4 5 6 7 8 9 100 1 2 3
2 3 4 5 6 7 8-2 -1 0 1
10 2 3 4 5 6 7 8 9-1
Module 2 85 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany
Reflect
8 What is a short method to write the compound inequality x ge 0 AND x lt 6
Your Turn
Write the compound inequality shown by each graph
9
10
Explain 4 Expressing Acceptable Levels with Compound Inequalities
You can express quality-controls levels in real-world problems using compound inequalities
Example 4 Write a compound inequality to represent the indicated quality-control level and graph the solutions
A The recommended pH level for swimming pool water is between 72 and 76 inclusive
Let p be the pH level of swimming pool water
72 is less than or equal to pH level is less than or equal to 76
72 le p le 76
The compound inequality is 72 le p le 76
Graph the solutions
0-10 -8-9 -7-6 -5-4 -3 -2 -1
71 72 73 74 75 76 77 78 79 8070
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 86 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
copy H
oug
hton
Mif
flin
Har
cour
t Pub
lishi
ng
Com
pan
y
B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany
bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
copy H
oug
hton
Mif
flin
Har
cour
t Pub
lishi
ng
Com
pan
y
Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany bull Im
age C
redits copy
Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton
Mif
flin
Har
cour
t Pub
lishi
ng
Com
pan
y bull I
mag
e C
red
its
copy
bik
erid
erlo
nd
onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany
The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton
Mif
flin
Har
cour
t Pub
lishi
ng
Com
pan
y
Your Turn
Solve each compound inequality and graph the solutions
6 x - 5 ge -2 OR x -5 le -6
7 4x -1 lt 15 OR 8x ge 48
Explain 3 Creating Compound Inequalities From GraphsGiven a number line graph with a solution set graphed you can create a compound inequality to fit the graph
Example 3 Write the compound inequality shown by each graph
A
The shaded portion of the graph is not between two values so the compound inequality involves OR
On the left the graph shows an arrow pointing left from -1 and a solid circle so use le
The inequality is x le -1
On the right the graph shows an arrow pointing right from 7 and a solid circle so use ge
The inequality is x ge 7
The compound inequality is x le -1 OR x ge 7
B
The graph is shaded between the values and so the compound inequality involves AND
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The graph is shaded to the rightleft of and the circle is opensolid so use the inequality
symbol
The inequality is
The compound inequality is
-1 0 1 2 3 4 5-5-4 -3 -2
4 5 6 7 8 9 100 1 2 3
2 3 4 5 6 7 8-2 -1 0 1
10 2 3 4 5 6 7 8 9-1
Module 2 85 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany
Reflect
8 What is a short method to write the compound inequality x ge 0 AND x lt 6
Your Turn
Write the compound inequality shown by each graph
9
10
Explain 4 Expressing Acceptable Levels with Compound Inequalities
You can express quality-controls levels in real-world problems using compound inequalities
Example 4 Write a compound inequality to represent the indicated quality-control level and graph the solutions
A The recommended pH level for swimming pool water is between 72 and 76 inclusive
Let p be the pH level of swimming pool water
72 is less than or equal to pH level is less than or equal to 76
72 le p le 76
The compound inequality is 72 le p le 76
Graph the solutions
0-10 -8-9 -7-6 -5-4 -3 -2 -1
71 72 73 74 75 76 77 78 79 8070
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 86 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
copy H
oug
hton
Mif
flin
Har
cour
t Pub
lishi
ng
Com
pan
y
B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany
bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
copy H
oug
hton
Mif
flin
Har
cour
t Pub
lishi
ng
Com
pan
y
Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany bull Im
age C
redits copy
Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton
Mif
flin
Har
cour
t Pub
lishi
ng
Com
pan
y bull I
mag
e C
red
its
copy
bik
erid
erlo
nd
onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany
The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany
Reflect
8 What is a short method to write the compound inequality x ge 0 AND x lt 6
Your Turn
Write the compound inequality shown by each graph
9
10
Explain 4 Expressing Acceptable Levels with Compound Inequalities
You can express quality-controls levels in real-world problems using compound inequalities
Example 4 Write a compound inequality to represent the indicated quality-control level and graph the solutions
A The recommended pH level for swimming pool water is between 72 and 76 inclusive
Let p be the pH level of swimming pool water
72 is less than or equal to pH level is less than or equal to 76
72 le p le 76
The compound inequality is 72 le p le 76
Graph the solutions
0-10 -8-9 -7-6 -5-4 -3 -2 -1
71 72 73 74 75 76 77 78 79 8070
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 86 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
copy H
oug
hton
Mif
flin
Har
cour
t Pub
lishi
ng
Com
pan
y
B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany
bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
copy H
oug
hton
Mif
flin
Har
cour
t Pub
lishi
ng
Com
pan
y
Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany bull Im
age C
redits copy
Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton
Mif
flin
Har
cour
t Pub
lishi
ng
Com
pan
y bull I
mag
e C
red
its
copy
bik
erid
erlo
nd
onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany
The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton
Mif
flin
Har
cour
t Pub
lishi
ng
Com
pan
y
B The recommended free chlorine level for swimming pool water is between 10 and 30 parts per million inclusive
Let c be the free chlorine level in the pool
is less than or equal to free chlorine level is less than or equal to
c
The compound inequality is le c le
Graph the solutions
Reflect
11 Discussion What does the phrase ldquobetween 72 and 76 inclusiverdquo mean
Your Turn
Write a compound inequality to represent the indicated quality-control level and graph the solutions
12 The recommended alkalinity level for swimming pool water is between 80 and 120 parts per million inclusive
Elaborate
13 Explain the difference between graphing a compound inequality involving AND and graphing a compound inequality involving OR
14 How can you tell whether a compound inequality involves AND or OR from looking at its graph
15 Essential Question Check-In Explain how to find the solutions of a compound inequality
1 2 3 4 5 6 7 8 9 100
40 80 120 160 2000
Module 2 87 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany
bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
copy H
oug
hton
Mif
flin
Har
cour
t Pub
lishi
ng
Com
pan
y
Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany bull Im
age C
redits copy
Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton
Mif
flin
Har
cour
t Pub
lishi
ng
Com
pan
y bull I
mag
e C
red
its
copy
bik
erid
erlo
nd
onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany
The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany
bull Online Homeworkbull Hints and Helpbull Extra Practice
Complete the truth tables
1
P QP
True or FalseQ
True or FalseP AND Q
True or False
An apple is a fruitA carrot is a vegetable
An apple is a fruit A carrot is a fruit
An apple is a vegetable
A carrot is a vegetable
An apple is a vegetable
A carrot is a fruit
2
P QP
True or FalseQ
True or FalseP OR Q
True or False
Blue is a color Five is a number
Blue is a color Five is a color
Blue is a number Five is a number
Blue is a number Five is a color
Solve each compound inequality and graph the solutions
3 -3 lt 3x le 9 4 0 le 2x - 10 le 20
5 x - 5 lt 3 OR x - 5 ge 8 6 1 le x + 7 lt 7
7 4x + 3 lt -5 OR 4x + 3 gt 23 8 x _ 5 - 2 le - 6 OR 8x + 1 ge 41
9 -6 lt x - 12 _ 4 lt - 2 10 x + 7 le 7 OR 5 + 2x gt 7
Evaluate Homework and Practice
-1 0 1 2 3 4 5-5-4 -3 -2 -10 0 10 20-20
9 10 11 12 13 14 155 6 7 8 210-8 -7-6 -5-4 -3 -2 -1
750 1 2 3 4 6-3 -2 -1 2010-10 0-30 -20
-4 0 4-12 -8 -1 0 1 2 3 4 5-5-4 -3 -2
Module 2 88 Lesson 5
DO NOT EDIT--Changes must be made through File infoCorrectionKey=NL-BCA-B
copy H
oug
hton
Mif
flin
Har
cour
t Pub
lishi
ng
Com
pan
y
Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany bull Im
age C
redits copy
Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton
Mif
flin
Har
cour
t Pub
lishi
ng
Com
pan
y bull I
mag
e C
red
its
copy
bik
erid
erlo
nd
onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany
The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton
Mif
flin
Har
cour
t Pub
lishi
ng
Com
pan
y
Write the compound inequality shown by each graph
11
12
13
14
15
16
2 3 4 5 6 7 8-2 -1 0 1
0-10 -8-9 -7-6 -5-4 -3 -2 -1
6 7 8 9 10 11 12 13 14 155
0 1 2 3 4 5 6-4 -3 -2 -1
1 2 3 4 5 6 7 8 9 100
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 89 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany bull Im
age C
redits copy
Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton
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flin
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bik
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HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany
The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany bull Im
age C
redits copy
Than
apo
l Kup
tanisakornA
lamy
Write a compound inequality to show the levels that are within each range Then graph the solutions
17 Biology An iguana needs to live in a warm environment The temperature in a pet iguanarsquos cage should be between 70 degF and 95 degF inclusive
18 Meteorology One layer of Earthrsquos atmosphere is called the stratosphere At one point above Earthrsquos surface the stratosphere extends from an altitude of 16 kilometers to an altitude of 50 kilometers
19 Music A typical acoustic guitar has a range of three octaves When the guitar is tuned to ldquoconcert pitchrdquo the range of frequencies for those three octaves is between 824 Hertz and 6592 Hertz inclusive
20 Transportation The cruise-control function on Georginarsquos car should keep the speed of the car within 3 miles per hour of the set speed The set speed is 55 miles per hour
21 Chemistry Water is not a liquid if its temperature is above 100 degC or below 0 degC
22 Sports The ball used in a soccer game may not weigh more than 16 ounces or less than 14 ounces at the start of the match After 15 ounces of air were added to a ball the ball was approved for use in a game
23 Match the compound inequalities with the graphs of their solutions
A -26 lt 6x - 8 lt 16
B - 1 _ 3 le x + 2 _ 3 le 2
C 4x + 1 lt -11 OR x _ 2 - 5 gt -3
D x - 6 _ 3 le -3 OR 2x + 8 ge 16
55 60 65 70 75 80 85 90 95 10050
5 10 15 20 25 30 35 40 45 500
200 400 600 800 10000
51 52 53 54 55 56 57 58 59 6050
160120400 80
11 12 13 14 1510
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
-1 0 1 2 3 4 5-5-4 -3 -2
Module 2 90 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton
Mif
flin
Har
cour
t Pub
lishi
ng
Com
pan
y bull I
mag
e C
red
its
copy
bik
erid
erlo
nd
onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany
The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton
Mif
flin
Har
cour
t Pub
lishi
ng
Com
pan
y bull I
mag
e C
red
its
copy
bik
erid
erlo
nd
onS
hutt
erst
ock
HOT Focus on Higher Order Thinking
24 Multi-Step Jennarsquos band is going to record a CD at a recording studio They will pay $225 to use the studio for one day and $80 per hour for sound technicians Jenna has $200 and can reasonably expect to raise up to an additional $350 by taking pre-orders for the CDs
a Explain how the inequality 200 le 225 + 80n le 550 can be used to find the number of hours Jenna and her band can afford to use the studio and sound technicians
b Solve the inequality Are there any numbers in the solution set that are not reasonable in this situation
c Suppose Jenna raises $350 in pre-orders How much more money would she need to raise if she wanted to use the studio and sound technicians for 6 hours
25 Explain the Error A student solves the compound inequality 15 le 2x + 5 le 17 and finds the solutions of the compound inequality to be all real numbers Explain and correct the studentrsquos mistake Graph the actual solutions to back up your answer
26 Communicate Mathematical Thinking Describe the solutions of the compound inequalities x gt 9 AND x lt 9
x lt 9 OR x gt 9
x ge 9 AND x le 9
x le 9 OR x ge 9
1 2 3 4 5 6 7 8 9 100
Module 2 91 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany
The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B
copy H
oug
hton Mifflin H
arcourt Publishin
g Com
pany
The table gives the melting point and boiling point of various elements Write a compound inequality for each element to show the temperature range of the element in its liquid state Graph the solutions of each Suppose you were to set the temperature of each element to its melting point and increase the temperature of each element at the same rate Which element will remain liquid for the longest amount of time Which element will reach its boiling point first Explain
Element Melting Point (degC) Boiling Point (degC)
Gold 1064 2856
Copper 1085 2562
Iron 1538 2861
Lead 327 1749
Aluminum 660 2519
Gold
Copper
Iron
Lead
Aluminum
Lesson Performance Task
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
0 600 1200 1800 2400 3000
Module 2 92 Lesson 5
DO NOT EDIT--Changes must be made through File info CorrectionKey=NL-BCA-B